Klinefelter Syndrome Research Articles

The Use of Genomic Screening for the Detection of Chromosomal Abnormalities in the Domestic Horse: Five New Cases of 65,XXY Syndrome in the Pura Raza Español Breed.

Sex chromosomal abnormalities are a well-established cause of reproductive failure in domestic horses. Because of its difficult diagnosis, the Pura Raza Español breeding program established a routine screening for chromosomal abnormalities in all the horses prior to enrolling in the studbook. This genomic procedure combines an initial assessment based on the results from Short Tandem Repeat (STR) parentage testing followed by a Single-Nucleotide Polymorphism (SNP) based copy number aberration (CNA) confirmative analysis in positive cases. Using this methodology, we identified five new individuals carrying a 65,XXY chromosomal number aberration (CNA) among 27,330 foals enrolled over the past two reproductive seasons. The animals were initially flagged as CNA candidates due to abnormal results in STR testing. Subsequent analysis genotyping using an STR sex-linked dedicated panel and a medium-density SNP array in ECAX and ECAY confirmed the diagnosis as 65,XXY carriers. Four cases (upon sample availability) underwent further analysis using in situ fluorescent hybridization with ECAX and ECAY probes, showing identical results. Phenotypic analysis revealed abnormal gonad development in one of the cases, showing that the remaining four had a normal reproductive morphology. To our knowledge, this represents the largest number of horses exhibiting the equine form of Klinefelter syndrome (65,XXY) reported to date. Our study highlights the importance of genomic screening in the accurate detection of chromosomal abnormalities in horses.

Klinefelter syndrome in a patient with double Y-autosomal translocation

Klinefelter syndrome is one of the most common chromosomal abnormalities and the most common genetic cause of male infertility. About 85 % of patients have 47,XXY karyotype, other patients have other non-mosaic and mosaic Klinefelter syndrome variants. We report a unique clinical case — Klinefelter syndrome patient with double Y autosomal translocation. The proband is a 15-year-old male patient (height 180 cm, weight 50 kg, normal IQ) who was admitted for cytogenetic examination and genetic counseling due to delayed puberty. He was diagnosed with testicular hypoplasia, hypergonadotropic hypogonadism, pituitary microadenoma and left-sided varicocele. The proband was born in a nonconsanguineous marriage after in vitro fertilization due to paternal male factor infertility. Cytogenetic analysis was performed on cultured peripheral blood lymphocytes using standard chromosome analysis with GTG staining and FISH analysis. Molecular analysis of the Y chromosome was performed by multiplex PCR. Complex cytogenetic examination revealed a 46,XX,der(Y) t(Y;15)(q12;q11.1),der(13)t(Y;13)(q12;p11.2),-15 karyotype in the proband. Molecular analysis showed that the proband is SRY positive; no microdeletion of the Y chromosome was found. The detected double Y autosomal translocation is a chromosomal abnormality independent of KS. The father of the proband is an oligozoospermic man with robertsonian translocation 13;15 — 45,XY,der(13;15)(q10;q10), the mother has a normal karyotype 46,XX. Apparently, the der(13) and der(Y) chromosomes result from abnormal meiotic recombination in paternal meiosis between the heterochromatic region Yq12 and the centromeric/pericentromeric heterochromatin of chromosomes 13 and 15 involved in the paternal robertsonian translocation, and Klinefelter syndrome is due to the presence of two X chromosomes in the karyotype in the presence of a derivative Y chromosome. The detected double Y-autosomal translocation is a chromosomal abnormality unrelated to Klinefelter syndrome, arising on the background of the paternal robertsonian translocation.

MECP2 Variants in Males: More Common Than Previously Appreciated

ObjectiveTo assess the age and MECP2 variants of recently identified males and set the stage for further study of clinical features in males. MethodsGenetic information on the specific MECP2 variant was acquired from the coordinator (KF) of the Parent Group for Males. Data were collected indicating whether these variants were de novo or transmitted from the mother and whether males who appeared to meet the diagnostic criteria for Rett syndrome (RTT) had mosaicism for the MECP2 variant. ResultsFifty-nine males were identified through the parent group. Their ages ranged from 2 to 28 years, with the median age being 7.0 years and the mean age being 10.8 years. Of these variants, forty-six (78.0%) were de novo, nine (15.3%) were maternally inherited, and for four (6.8%), inheritance was not known. Eleven (18.6%) were mosaic, 10 with somatic mosaicism and one with Klinefelter syndrome (47XXY). Together with males reported previously from the US Natural History Study, the total group represents 85 males, of whom 27 are deceased. ConclusionThese data on males with MECP2 variants are important to caregivers, physicians, and researchers to begin to characterize their historical and clinical features, to improve diagnostic recognition and overall care, and to accelerate access to therapeutic studies including gene replacement strategies. Equal access to such therapies for males is critical.

Unraveling the puzzle of bone health in Klinefelter syndrome: association between dxa derived bone quality indexes and body composition parameters in a single center cohort

Unraveling the puzzle of bone health in Klinefelter syndrome: association between dxa derived bone quality indexes and body composition parameters in a single center cohort

Anogenital distance in klinefelter syndrome: a case-control study

Anogenital distance in klinefelter syndrome: a case-control study

Testicular mosaicism in non-mosaic postpubertal Klinefelter patients with focal spermatogenesis and in non-mosaic prepubertal Klinefelter boys.

Do testis-specific cells have a normal karyotype in non-mosaic postpubertal Klinefelter syndrome (KS) patients with focal spermatogenesis and in non-mosaic prepubertal KS boys? Spermatogonia have a 46, XY karyotype, and Sertoli cells surrounding these spermatogonia in postpubertal patients also have a 46, XY karyotype, whereas, in prepubertal KS boys, Sertoli cells surrounding the spermatogonia still have a 47, XXY karyotype. A significant proportion of patients with non-mosaic KS can have children by using assisted reproductive techniques thanks to focal spermatogenesis. However, the karyotype of the cells that are able to support focal spermatogenesis has not been revealed. Testicular biopsy samples from non-mosaic KS patients were included in the study. Karyotyping for sex chromosomes in testis-specific cells was performed by immunohistochemical analysis of inactive X (Xi) chromosome and/or fluorescent in situ hybridization (FISH) analysis of chromosomes 18, X, and Y. A total of 22 KS patients (17 postpubertal and 5 prepubertal) who were non-mosaic according to lymphocyte karyotype analysis, were included in the study. After tissue processing, paraffin embedding, and sectioning, the following primary antibodies were used for cell-specific analysis and Xi detection; one section was stained with MAGE A4 for spermatogonia, SOX9 for Sertoli cells, and H3K27me3 for Xi; the other one was stained with CYP17A1 for Leydig cells, ACTA2 for peritubular myoid cells, and H3K27me3 for Xi. Xi negative (Xi-) somatic cells (i.e. Sertoli cells, Leydig cells, and peritubular myoid cells) were evaluated as having the 46, XY karyotype; Xi positive (Xi+) somatic cells were evaluated as having the 47, XXY. FISH stain for chromosomes 18, X, and Y was performed on the same sections to investigate the karyotype of spermatogonia and to validate the immunohistochemistry results for somatic cells. According to our data, all spermatogonia in both postpubertal and prepubertal non-mosaic KS patients seem to have 46, XY karyotype. However, while the Sertoli cells surrounding spermatogonia in postpubertal samples also had a 46, XY karyotype, the Sertoli cells surrounding spermatogonia in prepubertal samples had a 47, XXY karyotype. In addition, while the Sertoli cells in some of the Sertoli cell-only tubules had 46, XY karyotype, the Sertoli cells in some of the other Sertoli cell-only tubules had 47, XXY karyotype in postpubertal samples. In contrast to the postpubertal samples, Sertoli cells in all tubules in the prepubertal samples had the 47, XXY karyotype. Our data also suggest that germ cells lose the extra X chromosome during embryonic, fetal, or neonatal life, while Sertoli cells lose it around puberty. Peritubular myoid cells and Leydig cells may also be mosaic in both postpubertal patients and prepubertal boys, but it requires further investigation. The number of prepubertal testicle samples containing spermatogonia is limited, so more samples are needed for a definitive conclusion. The fact that not all the cell nuclei coincide with the section plane limits the accurate detection of X chromosomes by immunohistochemistry and FISH in some cells. To overcome this limitation, X chromosome analysis could be performed by different techniques on intact cells isolated from fresh tissue. Additionally, there is no evidence that X chromosome inactivation reoccurs after activation of the Xi during germ cell migration during embryogenesis, limiting the prediction of X chromosome content in germ cells by H3K27me3. Our findings will lay the groundwork for new clinically important studies on exactly when and by which mechanism an extra X chromosome is lost in spermatogonia and Sertoli cells. This study was funded by The Scientific and Technological Research Council of Türkiye (TUBITAK) (2219 - International Postdoctoral Research Fellowship Program for Turkish Citizens) and the Strategic Research Program (SRP89) from the Vrije Universiteit Brussel. The authors declare no competing interests. N/A.

Differences In The Qualitative Features Of Dermatoglyphs Between Persons With Turner And Klinefelter Syndromes And Those With A Normal Karyotype

: Individuals with numerical abnormalities in the X and Y chromosomes are ideal candidates for studying the impact of these chromosomes on the development of specific dermatoglyphic characteristics in humans. The aim of this study is to identify differences in the qualitative features of dermatoglyphs in the Albanian population of Kosovo between women with Turner syndrome and women with a normal karyotype, as well as between men with Klinefelter syndrome and men with a normal karyotype.

Exploring suicidal attempts in a rare case of Klinefelter syndrome comorbid with autism spectrum disorder: Unveiling the underdiagnosed nexus and noble intervention of electroconvulsive therapy

Exploring suicidal attempts in a rare case of Klinefelter syndrome comorbid with autism spectrum disorder: Unveiling the underdiagnosed nexus and noble intervention of electroconvulsive therapy

Advances in genetic research on Non-syndromic congenital joint synostosis

Congenital joint synostosis (CJS) is a functional impairment resulting from failure in joint morphogenesis during embryonic development. Clinically, it may be classified as syndromic (sCJS) and non-syndromic (nsCJS) disorders. Common sCJS include chromosomal disorders such as Klinefelter syndrome and single-gene disorders like Apert/Pfeiffer/Crouzon syndromes, Holt-Oram syndrome, Ehlers-Danlos syndrome, and Radial-ulnar synostosis with thrombocytopenia, presenting with multiple system/organ anomalies. By contrast, nsCJS manifest with only joint abnormalities, affecting one or multiple joints. This review has focused on human nsCJS and its genetic etiology. To date, variants in seven genes (NOG, GDF5, FGF9, GDF6, FGF16, SMAD6, and MECOM) have been identified as causative factors for nsCJS. This review has focused on such genes and provided a comprehensive review for the clinical phenotypes, genetic patterns, common variants, and underlying mechanisms associated with nsCJS based on a literature review. In addition, it has also analyzed other candidate genes for nsCJS within the context of relevant signaling pathways involved in joint morphogenesis.

How exome sequencing improves the diagnostics and management of men with non-syndromic infertility.

Male infertility affects approximately 17% of all men and represents a complex disorder in which not only semen parameters such as sperm motility, morphology, and number of sperm are highly variable, but also testicular phenotypes range from normal spermatogenesis to complete absence of germ cells. Genetic factors significantly contribute to the disease but chromosomal aberrations, mostly Klinefelter syndrome, and microdeletions of the Y-chromosome have remained the only diagnostically and clinically considered genetic causes. Monogenic causes remain understudied and, thus, often unidentified, leaving the majority of the male factor couple infertility pathomechanistically unexplained. This has been changing mostly because of the introduction of exome sequencing that allows the analysis of multiple genes in large patient cohorts. As a result, pathogenic variants in single genes have been associated with non-syndromic forms of all aetiologic sub-categories in the last decade. This review highlights the contribution of exome sequencing to the identification of novel disease genes for isolated (non-syndromic) male infertility by presenting the results of a comprehensive literature search. Both, reduced sperm count in azoospermic and oligozoospermic patients, and impaired sperm motility and/or morphology, in asthenozoospermic and/or teratozoospermic patients are highly heterogeneous diseases with well over 100 different candidate genes described for each entity. Applying the standardized evaluation criteria of the ClinGen gene curation working group, 70 genes with at least moderate evidence to contribute to the disease are highlighted. The implementation of these valid disease genes in clinical exome sequencing is important to increase the diagnostic yield in male infertility and, thus, improve clinical decision-making and appropriate genetic counseling. Future advances in androgenetics will continue to depend on large-scale exome and genome sequencing studies of comprehensive international patient cohorts, which are the most promising approaches to identify additional disease genes and provide reliable data on the gene-disease relationship.

Experience in the use of circular incision bi-pedicled vertical flap based mastectomy for grade III gynecomastia: A case series

Introduction and importanceSurgical management of grade III gynecomastia with excess redundant skin is challenging. The choice of the surgical technique is mainly decided upon the size of the gynecomastia, the skin redundancy and correction of nipple position. Case presentationWe report our experience in the use of the circular incision bi-pedicled vertical flap based mastectomy for grade III gynecomastia according to Simon classification. This is a retrospective study conducted between January 2022 and April 2023 at two selected units in Sri Lanka. Clinical discussionA total of 7 patients with bilateral grade III gynecomastia were included in this study with a median age of 24 years (range: 18–42 years). The mean BMI was 23.2 kg/m2. All patients exhibited near symmetrical breasts and large areolar diameters. All patients complained of physical and psychological dissatisfaction with their condition and sought an aesthetic correction. Two patients were diagnosed with Klinefelter syndrome and others were apparently healthy. The main complication was seroma formation (7/7). No patients developed haematoma. Nipple hypothesia was noted in two patients which improved on follow up. The mean follow- up duration was 4–9 months. The survey of patient satisfaction showed 9 for contour, 8.6 for wound scars, 9.2 for overall satisfaction and 9.6 for improvement in self-confidence. ConclusionThe above surgical technique achieved satisfactory aesthetic results while avoiding unsightly scars or serious complications and can be considered in the surgical decision making for grade III gynecomastia.

A qualitative exploration of experiences of gender identity and gender questioning among adults with Klinefelter syndrome/XXY.

People with Klinefelter syndrome (KS/XXY) may be at higher risk of gender dysphoria than the general population and gender diversity needs greater recognition and consideration in services for people affected. This study aimed to give systematic insights into experiences of gender diversity among people with KS/XXY, which could inform more person-centered care for people with KS/XXY and contribute to practical guidance for healthcare professionals. We conducted individual, semi-structured interviews with 11 adults with diagnosed KS/XXY. The verbatim interview transcripts were analyzed using experiential reflexive thematic analysis, which identified four themes: (1) Experience of gender, which described participants' experiences of exploring and negotiating their gender identity; (2) Navigating expectations, which described how participants' gender uncertainty was associated with confusion, isolation, and shame, and how fears about other people's reactions caused participants to keep their gender identity secret; (3) Testosterone assumptions, which described how participants needed more discussion and counseling before testosterone replacement therapy (TRT), and how some benefited from treatment with alternative hormones to testosterone; and (4) A different approach, which described participants' experiences of care at gender identity clinics. The findings give new insights into the gender identity journeys of people with KS/XXY, from early attempts to understand and make sense of gender, through dealing with social pressures, the development of gender identities more congruent with feelings, and experiences with hormone replacement therapy. The practice implications include that there should be improved consideration of gender identity in care for KS/XXY, better psychological support for those affected by gender diversity, and more consideration given to alternatives to testosterone-based therapies. Future research could explore the experiences of gender identity among different groups of people with KS/XXY, the development of gender identity over time, the effects of TRT on gender identity, and healthcare providers' knowledge and attitudes about gender identity and KS/XXY.

Second chance in fertility: a comprehensive narrative review of redo micro-TESE outcomes after initial failure.

When microdissection testicular sperm extraction (micro-TESE) fails, a redo procedure may be the only option for patients who want a biological child. However, there are many gaps of knowledge surrounding the procedure, which need to be addressed to help clinicians and patients make informed decisions. This review explores redo micro-TESE in the context of nonobstructive azoospermia (NOA). Literature was searched using Google Scholar, Medline, and PubMed. Search terms were "NOA" AND "second microdissection testicular sperm extractions" AND "redo microdissection testicles sperm extraction" AND "repeat microdissection testicular sperm extractions" AND "failed microdissection testicular sperm extractions" AND "salvage microdissection testicular sperm extractions". Only original articles in English were included. A total of nine articles were included, consisting of four retrospective and five prospective studies. The time gap between the first and second micro-TESE varied from 6 months to 24 months. Most of the included studies reported successful surgical sperm retrieval (SSR) in the second micro-TESE in the range of 10%-21%, except in one study where it reached 42%. It has not been presented any definitive information about the use of hormonal treatment or the benefit of varicocelectomy prior to the second micro-TESE. Patients with hypospermatogenesis and Klinefelter syndrome (KS) had the highest chance of success in redo surgery. In conclusion, redo micro-TESE following a negative procedure can lead to sperm recovery in 10%-21%. Patients with hypospermatogenesis and KS have a higher chance of success. There is no enough evidence to conclude which is the best hormonal stimulation if any before a redo surgery.

Exome sequencing confirms the clinical diagnosis of both joubert syndrome and klinefelter syndrome with keratoconus in a han Chinese family.

Joubert syndrome a rare genetic disorder, is characterized by abnormalities in the development of the central nervous system with "molar signs" on magnetic resonance imaging of the brain and accompanied by cerebellar vermis hypoplasia, ataxia, hypotonia, and developmental delay. Keratoconus (KC) is a kind of genetically predisposed eye disease that causes blindness characterized by a dilated thinning of the central or paracentral cornea conically projected forward, highly irregular astigmatism, and severe visual impairment. Klinefelter syndrome is caused by an extra X chromosome in the cells of male patients, and the main phenotype is tall stature and dysplasia with secondary sex characteristics. This study was intended to identify the genetic etiology and determine the clinical diagnosis of one Han Chinese family with specific clinical manifestations of keratoconus and multiorgan involvement. A comprehensive ocular and related general examination was performed on one patient and his asymptomatic parents and brother. Pathogenic genes were tested by exome sequencing. CNV-seq was used to verify the copy number variation, and peripheral blood was cultured for karyotype analysis. The pathogenicity of the identified variant was determined subject to ACMG guidelines. The Gene Expression Omnibus (GEO) dataset of keratoconus-related genes in the NCBI database was obtained to analyze the differentially expressed genes in corneal tissues of the keratoconus group and the normal control group, and analysis of protein-protein interaction networks (PPI) was performed. Proband, a 25-year-old male, had sudden loss of vision in the left eye for 1 week. Best corrected visual acuity (BCVA): 0.5 (-1.00DS/-5.00DC*29°) in the right eye, counting fingers/40cm in the left eye. Slit-lamp microscopy of the right eye showed mild anterior protrusion of the cornea and thinning of the cone-topped cornea. The left eye showed marked thinning of the central region of the cornea, rounded edema in the form of a cone-like bulge, epithelial bullae, edema and turbidity of the stroma, and bulging of the Descemet's membrane. Cranial magnetic resonance imaging (MRI) revealed changes in the midbrain and cerebellum, with a "molar sign" and a "bat-winged" ventriculus quartus cerebri. General check-up: 168cm in height, decreased muscle tone in all four limbs, knee jerk elicited, negative Babinski sign, abdominal reflexes elicited, finger-to-nose test positive, intentional tremor evident in both hands, positive Romberg's sign, instability of gait, level I intellectual disability, poor adaptive behavior, communication disorders, teeth all dentures, a peculiar face with blepharophimosis, wide inner canthus distance, mild ptosis, severe positive epicanthus, high palatal arches, exotropia, hypotrichosis of beard and face, inconspicuous prominentia laryngea, and short upper and lower limbs. Exome sequencing detected compound heterozygous frameshift variants M1:c.9279dup:p.His3094Thrfs*18 and M2:c.6515_6522del:p.Lys2172Thrfs*37 in the patient's CPLANE1 gene and the presence of duplication-type CNV on the X chromosome. Sanger sequencing showed that the mother and father carried the M1 and M2 variants, respectively, and the younger brother carried the M2 variant, which was a novel variant. CNV-seq analysis showed the presence of a duplication-type CNV Xp22.33-Xq28 (2757837-156030895) of approximately 155Mb on the X chromosome of the proband, which was a de novo variant and carried by neither of the parents. The two heterozygous frameshift variants and duplication-type CNV were pathogenic according to the ACMG guidelines. Differential expression analysis of keratoconus-related genes showed that CPLANE1 was upregulated in the corneal tissues of keratoconus patients compared with normal controls, and such a difference was statistically significant (p = 0.000515, <0.05). PPI analysis showed that the CPLANE1-NPHP3 complex protein acted as a bridge between cilia and extracellular matrix tissue. According to the genetic test results and clinical phenotype analysis, the family was finally diagnosed with Joubert syndrome combined with Keratoconus and Klinefelter syndrome. In this study, we report a proband in a Han Chinese family with both Joubert syndrome and X-linked Klinefelter syndrome as well as keratoconus, and the phenotype spectrum of CPLANE1-Joubert syndrome may be expanded accordingly. Meanwhile, the significance of exome sequencing was emphasized in aiding the clinical diagnosis of complex cases, which is difficult to make.

Medical Findings in Infants Prenatally Identified with Sex Chromosome Trisomy in Year One of Life.

Sex chromosome trisomies (SCT), including XXY, XYY, and XXX syndromes, have been historically underdiagnosed. Noninvasive prenatal cell-free DNA screening has significantly increased identification of these conditions, leading to a need for pediatric care for a growing population of newborns with SCT. Our goal was to analyze and compare perinatal features, medical diagnoses, and physical features in infants with prenatal identification of SCT conditions through the first year of life. The eXtraordinarY Babies Study is an ongoing, prospective natural history study of prenatally identified children with SCT conducted by interdisciplinary teams in Colorado and Delaware. Participants were enrolled prior to 12 months of age and had pregnancy, birth, medical histories, and physical exams completed by board-certified pediatricians at 2, 6, and/or 12-month visits. Descriptive statistics were followed by comparisons between SCT groups using t-tests or ANOVA, Fisher exact, and correlations between medical features with alpha of 0.05. Relative risks were calculated compared to general population rates. 327 infants were included in the analysis (XXY=195, XXX=79, XYY=53). Major congenital anomalies were rare (1.7%). Relative risk compared to general population was elevated for breastfeeding difficulties (51.7%;RR 2.7), positional torticollis (28.2%;RR 7.2), eczema (48.0%;RR 3.5), food allergies (19.3%;RR 2.4), constipation requiring intervention (33.9%;RR 7.6), small cardiac septal defects (7.7%;RR 17.2), and structural renal abnormalities (4.4%;RR 9.7). Inpatient hospitalization was required for 12.4%, with 59.5% of hospitalizations attributable to respiratory infections. These findings of medical conditions with a higher prevalence can inform anticipatory guidance and medical management for pediatricians caring for infants with SCT. Medical findings in largest cohort of prenatally identified infants with XXY, Trisomy X, and XYY from birth to 12 months and implications for pediatric care.What's Known on This Subject: One in ∼500 individuals have an extra X or Y chromosome, or sex chromosome trisomy (SCT). Prenatal screening is now routinely identifying SCT, however there are few studies to guide perinatal and infant care for these individuals.What This Study Adds: This prospective observational study presents medical features for 327 infants with prenatally identified SCT from birth through the first year of life. Results identify where proactive screenings and/or interventions may be warranted for infants with SCT.

P-022 Klinefelter syndrome couples are expected higher live birth rates than unexplained NOA couples after ICSI with testicular spermatozoa

Abstract Study question What are sperm retrieval rates (SRR) by microdissection TESE (micro TESE), fertilization rates, and pre- and post- implantation development in Klinefelter syndrome (KS) couples? Summary answer In KS couples, SRR, clinical pregnancy rates (CPR) per embryo transfer (ET), and live birth rates (LBR) per patient were higher than unexplained NOA couples. What is known already Micro TESE, in combination with ICSI, is presently used to treat infertility in cases of NOA including KS, which is the most common sex-chromosome disorder among infertile males, with a prevalence of 1 in 660 men and is a frequent cause of hypogonadism and infertility. There were few reports regarding ICSI outcomes in the couples of KS. The aim of this study is to assess the prevalence and the significance including SRR by micro TESE of ICSI outcomes with embryonic development in KS couples. Study design, size, duration A retrospective study was conducted in 212 patients with non-mosaic KS and 963 unexplained NOA patients with 46, XY without past history (unexplained NOA; not including after orchidopexy, KS, cryptozoospermia, post chemotherapy, mumps orchitis, etc) who underwent micro TESE and ICSI with fresh or cryopreserved testicular spermatozoa for their wives between September 2013 to November 2023. Participants/materials, setting, methods A total of 2204 azoospermic patients were examined for chromosomal analysis. We evaluated SRR of microdissection TESE, two pronuclei (2PN) rates, blastocyst development rates, good-quality blastocyst (Grade 3BB and above on day 5 by the Gardner scoring) rates, CPR per ET, and LBR per couple patient who underwent micro TESE. We did not undergo preoperative hormonal therapy for KS patients. Statistical analysis was performed using unpaired t-tests and chi-squared tests. Main results and the role of chance We identified 212 KS out of 2204 azoospermic patients (9.6%). SRR of the first attempt micro TESE in KS (91/175=52.0%) was significantly higher than unexplained NOA (166/768=21.6%) (p &amp;lt; 0.001). 2PN, blastocysts development, and good-quality blastocysts rates were 49.2%, 42.9%, 16.9% in KS and 50.8, 45.8%, 21.0% in unexplained NOA respectively. Only good-quality blastocysts rate of KS was significantly lower than that of unexplained NOA (p &amp;lt; 0.01). Taking into account deflection of wives age, each result was calculated at their age 38 or under, but they were the same. CPR and LBR per ET in KS (42.6%, 30.4%) were significantly higher than unexplained NOA (33.1%, 23.7%) (p &amp;lt; 0.01, p &amp;lt; 0.05). The couples were 26.4% (56/212) in KS and 12.0% (116/963) in unexplained NOA (p &amp;lt; 0.001) who have given birth or ongoing pregnancy up to now after underwent micro TESE. That is, KS couples were significantly easier to give birth than unexplained NOA. Rates of congenital disorders had no significant difference between KS and unexplained NOA. Limitations, reasons for caution We did not show the data using ejaculated sperm with KS. The natal outcomes and development of these children has not been fully investigated, long-term follow-up of babies of the KS couples is needed. Wider implications of the findings Micro TESE is particularly helpful for KS cases, but embryonic development depend on the quality of spermatozoa. However, if a blastocyst can be obtained, the expectation of having a child is considered to be high. These results were shown to be useful in informing azoospermic couples undergoing micro TESE. Trial registration number not applicable

P-007 Surgical sperm retrieval rate in men with Klinefelter syndrome is associated with testicular volume - but not with body constitution or Sertoli cell markers

Abstract Study question Do sperm retrieval and pregnancy rates in men with Klinefelter syndrome (KS) depend upon sperm retrieval method, age, testicular volume, body weight, and hormone concentrations? Summary answer Successful sperm retrieval was significantly associated with total testicular volume but not with sperm retrieval method, age, body weight, BMI, FSH, inhibin-B or AMH. What is known already Testicular sperm can be retrieved from approximately 40% of men with KS, resulting in an average pregnancy rate of 16%. The sperm retrieval rate seems to be unrelated to the age of the man and to preoperative FSH-levels. A decrease in testosterone concentration is usually observed 3 months after surgery. Possible negative effects of testosterone substitution therapy prior to surgery and the predictive value of body constitution, testicular volume and the Sertoli cell markers, AMH and inhibin-B, for sperm retrieval success in KS men are only partly known. Study design, size, duration A total of 14 KS patients underwent subcapsular orchiectomy and 34 KS patients underwent m-TESE at Centre of Andrology &amp; Fertility Clinic, Odense University Hospital. Pre-surgery examination included ultrasonography of the testicles, genetic analyses (standard chromosome analysis and screening for Y microdeletions and CFTR variants) and hormone analyses (including FSH, LH, testosterone, estradiol, prolactin, TSH, AMH, inhibin-B). Testosterone, LH, and FSH were also measured 3 months after surgery. Participants/materials, setting, methods Forty-three men had a 47,XXY karyotype, while 5 (2 from the subcapsular group and 3 from the m-TESE group) had a mosaic karyotype including 47,XXY. Subcapsular orchiectomy was performed unilaterally, while m-TESE was usually performed bilaterally. To avoid freezing the sperm retrieved, oocytes from the female partner was aspirated and vitrified after FSH-stimulation according to our usual IVF protocols. Oocytes were thawed on the day of sperm retrieval and embryos transferred in estrogen-progesterone stimulated cycles. Main results and the role of chance Sperm were obtained in 19 (40%) of the 48 men with KS. In 10 couples (21%) pregnancy was obtained and 7 women (15%) gave birth to at least one child resulting in ten children (6 girls and 4 boys), while one pregnancy is still ongoing. In the group who had a subcapsular orchiectomy, 5 (36%) had sperm retrieved, and pregnancy was obtained in 3 (20%) cases. Two gave birth to a child, while the third woman have had several abortions, most likely due to large fibromyomas of the uterus. In the m-TESE group 14 (41%) had sperm retrieved, and pregnancy was obtained in 7 (21%) cases. Five women (15%) gave birth to 8 children, while 1 pregnancy is still ongoing and the seventh experienced an early pregnancy loss. Furthermore, 3 couples have still not embryos transferred. Sperm were found in 3 men (60%) with mosaic karyotype. Sperm retrieval success was significantly associated with testicular volume (mean total testicular volumes of 3.4 mL vs. 2.3 mL; p &amp;lt; 0.01) but not with age, height, body weight, BMI or preoperative FSH, inhibin-B or AMH levels. Testosterone levels measured 3 months after the surgery, did not differ between men irrespective of surgical method. Limitations, reasons for caution The numbers of patients are limited and randomized studies with sufficient power are difficult to perform. AMH and inhibin-B, were only measured in the m-TESE group. Wider implications of the findings In KS patients, sperm retrieval and pregnancy rates were similar irrespective of the sperm retrieval method. Also serum testosterone 3 months postoperatively and cosmetic results experienced by patients were similar. Multicenter studies and larger studies are needed to provide more detailed information of the potential predictors for successful sperm retrieval. Trial registration number Not applicable

P-075 A new clinically relevant classification of seminiferous tubules in Klinefelter Syndrome patients based on the karyotype of the Sertoli cells

Abstract Study question Can a new seminiferous tubule classification be made that indicates the chance of sperm retrieval by TESE in Klinefelter Syndrome (KS) patients? Summary answer Spermatogonia are only present in tubules with euploid Sertoli cells. Classification of tubules based on Sertoli cell ploidy may predict sperm retrieval success with TESE. What is known already KS patients can have children thanks to focal spermatogenesis. However, this can only happen if sperm is produced. Histological classification of seminiferous tubules in these patients has been made based on the maturity of the Sertoli cells (type A and type B seminiferous tubules). However, so far there is no classification predicting the presence of germ cells. In case two X chromosomes are present, one is inactivated. The histone-3-lysine-27-tri-methylation (H3K27me3) protein is involved in X chromosome inactivation and its immunohistochemical staining may be used for a new seminiferous tubule classification based on the karyotype of Sertoli cells. Study design, size, duration Inactive X (Xi) chromosomes were immunohistochemically stained with H3K27me3 and seminiferous tubules were classified as Xi+ tubules (presence of inactive X in Sertoli cells) or Xi- tubules (absence of inactive X in Sertoli cells). Testicular biopsies were used from 17 non-mosaic KS adult patients. Participants/materials, setting, methods After tissue fixation, processing, and paraffin embedding, sections were cut at 5 µm. Immunohistochemical staining was applied with antibodies H3K27me3 (for inactive X chromosome), MAGE-A4 (for spermatogonia), and SOX9 (for Sertoli cells). Seminiferous tubules in testicular sections were classified as Xi+ or Xi- tubules and analyzed for the presence of spermatogonia or focal spermatogenesis. X chromosome number in spermatogonia and Sertoli cells was confirmed by the FISH method using chromosome 18, Y, and X probes. Main results and the role of chance A total of 311 (18±16) seminiferous tubule sections were analyzed in testicular tissue of 17 KS men. Of the 311 tubules analyzed, 253 (14±16) of the tubules were Xi- tubules and 58 (3±4) were Xi+ tubules. Spermatogonia were present in 41 of the Xi- tubules. As an exception, only one patient had spermatogonia in two Xi+ tubules, but these tubules were immature and spermatogenesis was not observed. Ongoing spermatogenesis was observed in two of Xi- tubules in one of the patients. Sixteen of the patients had both Xi- tubules and Xi+ tubules in their testicular sections. In 13 of these 16 patients with Xi- tubules, sperm was either obtained as a result of TESE or spermatogonia were observed in the Xi- tubules. Limitations, reasons for caution In Klinefelter patients, there are few seminiferous tubules due to widespread testicular fibrosis and degeneration of seminiferous tubules. Studies including more patient samples are needed for more definitive and comprehensive conclusions. Wider implications of the findings Spermatogonia are only present in tubules with euploid Sertoli cells. Therefore, we hypothesize that focal spermatogenesis only can occur in tubules with euploid Sertoli cells. Xi+ and Xi- seminiferous tubule classification based on H3K27me3 staining may thus be used to predict sperm production in KS patients. Trial registration number Not applicable

O-263 The risk of hypogonadism after microdissection testicular sperm extraction (micro TESE) in non-obstructive azoospermia (NOA) patients with various etiologies

Abstract Study question What is the risk factor of hypogonadism after micro TESE in NOA patients? Summary answer Klinefelter syndrome (KS), past history of cryptorchidism, preoperative testicular volume &amp;lt;8 ml or testosterone &amp;lt;287 ng/dL are significant risk factors of hypogonadism after micro TESE. What is known already Micro TESE combined with intracytoplasmic sperm injection (ICSI) is currently standard procedure to treat infertility in cases of NOA. Although many studies have reported the effectiveness of the treatment concerning about sperm retrieval rates (SRR) and the live birth rates, data on safety, especially on the risk of hypogonadism, are limited. Most previous studies, including our past study, regarding the risk of hypogonadism after TESE have been limited to relatively few in number of patients and the investigations only of the changes of mean serum testosterone levels. Study design, size, duration This study retrospectively investigated 535 NOA patients including 336 cases of unexplained NOA, 91 KS, 16 other chromosomal abnormalities, 31 azoospermia factor (AZF)c deletions, 31 past history of cryptorchidism, and 30 post anticancer chemotherapy, who had undergone micro TESE at our institution from September 2013 to August 2018. All of them had been examined serum follicle-stimulating hormone (FSH), luteinizing hormone (LH), and testosterone levels before and at least once in 1-3 months after micro TESE. Participants/materials, setting, methods In this study, hypogonadism was defined as total testosterone &amp;lt;250 ng/dL, which is established by the Japanese Society of Men’s Health as diagnostic criteria for late onset hypogonadism syndrome, and/or starting testosterone replacement therapy (TRT). We assessed risk factors of hypogonadism after micro TESE using indicators such as age, preoperative testicular volume and testosterone levels, past medical history, unilateral or bilateral, first time or not micro TESE. Main results and the role of chance In total of 535 men, FSH and LH after micro TESE significantly increased vs baseline (26.2 vs 29.9 IU/L, 9.6 vs 12.8 IU/L, respectively). On the other hand, testosterone levels significantly decreased after surgery (351.2 vs 297.5 ng/dL). Although postoperative hypogonadism was found in 42% (227/535), many of whom were cases of KS or preoperative testosterone levels &amp;lt;250 ng/dL. Sixteen men with KS, 3 men with unexplained NOA, and 2 men with past history of cryptorchidism started TRT because they complained clinical symptoms after micro TESE. Of the 21 men who started TRT, only 5 had new-onset low testosterone levels after micro TESE. According to the assessment of any association of various indicators and low postoperative total testosterone levels using multiple logistic regression analysis, significant risk factors of hypogonadism early after micro TESE were cases of KS (OR 11.4, 95% CI 4.4-29.9), preoperative testosterone levels &amp;lt;287 ng/dL (OR 7.5, 95% CI 4.7-12.0), preoperative testicular volume &amp;lt;8 ml (OR 3.9, 95% CI 2.3-6.4), past history of cryptorchidism (OR 2.9, 95% CI 1.1-7.8). Limitations, reasons for caution Most examinations of postoperative hormone levels were performed in short-term period after micro TESE, so we could only assess the risk of postoperative hypogonadism in a short time course in this cohort study. Wider implications of the findings The strength of the current study is that the risk factors of hypogonadism after micro TESE was assessed in a large population of NOA men with various etiologies. The results of this study provide useful clinical information about the risk of postoperative hypogonadism for NOA patients considering micro TESE. Trial registration number not applicable

P-090 Is preimplantation genetic testing for aneuploidy (PGT-A) necessary in the treatment strategy for ICSI with testicular sperm?

Abstract Study question Does the combination of testicular sperm extraction (TESE) and ICSI increase the risk of embryo aneuploidy? Summary answer Embryo aneuploidy occurrence is not increased when using testicular sperm and is not affected by the etiology of azoospermia. What is known already TESE-ICSI, especially in patients with non-obstructive azoospermia (NOA), has been reported to result in poor outcomes and difficulty in obtaining good blastocysts, which may be due to immature sperm retrieved by TESE. In addition, patients who require TESE have been shown to be at particularly high risk of chromosomally abnormal sperm. These factors may increase the risk of embryo aneuploidy in TESE-ICSI and contribute to poor outcomes. However, few reports have investigated the results of PGT-A following TESE-ICSI. This study was therefore designed to investigate whether using testicular sperm is more likely to result in embryo aneuploidy. Study design, size, duration This retrospective study included 81 couples and 197 TESE-ICSI cycles undergoing PGT-A (average maternal age: 38.1±5.4 years) between September 2016 and November 2023. Of the total cycles, 94 cycles were case of obstructive azoospermia (OA) and 53 cycles were cases of NOA. The etiologies of NOA included were unexplained (22 cycles), Klinefelter’s syndrome (KS) (10 cycles), post-chemotherapy (3 cycles), post-orchiopexy (11 cycles), and microdeletion of azoospermia factor (AZF) c on the Y chromosome (7 cycles). Participants/materials, setting, methods ICSI outcomes were compared between different etiologies (OA vs. NOA). A total of 356 blastocysts acquired were analyzed using PGT-A with next-generation sequencing (NGS). The PGT-A results were classified according to maternal age (&amp;lt;38, 38-41, &amp;gt;41 years) and paternal age (&amp;lt;40, ≥40 years). In addition, TESE-ICSI cycles were limited to the maternal age of &amp;lt; 38 years to remove the effect of maternal factors, the euploidy rates were compared between different etiologies or morphological grade. Main results and the role of chance The rates of fertilization and blastocyst formation for TESE-ICSI were significantly lower in NOA than OA (47.4% vs. 61.6%, P &amp;lt; 0.001 and 37.3% vs. 50.7%, P &amp;lt; 0.01, respectively). The rate of good-quality blastocyst (16.6% vs. 21.2%) was also lower, but not statistically significant. The euploidy rate of all evaluated TESE-ICSI embryos decreased with increasing maternal age (52.9% in &amp;lt; 38, 29.3% in 38-41, 10.0% in &amp;gt; 41 years), but was not affected by the paternal age (40.6% in &amp;lt; 40, 42.5% in ≥ 40 years). For cycles with the maternal age of &amp;lt; 38 years, the euploidy rate was not significantly different between OA and NOA patients (55.3% vs. 49.3%). In addition, the association between embryo euploidy and morphological grade (using Gardner’s classification, ≥BB for good-quality vs. &amp;lt;BB for poor-quality embryos) was evaluated, and the euploidy rate was significantly higher in good-quality embryos compared to poor-quality embryos (60.3% vs. 33.3%, P &amp;lt; 0.01). These results indicate the frequency of embryo aneuploidy in TESE-ICSI is comparable to commonly used ejaculated sperm. Furthermore, it suggests that embryo aneuploidy is dependent on maternal age or morphological grade of embryo, but not on paternal age or the etiology of azoospermia. Limitations, reasons for caution Patients with chromosomal abnormalities, i.e. KS, could not be evaluated due to the small number of cases and patients with chromosomal translocation were not included in this study. Therefore, the effects of male factors in NOA on embryo aneuploidy require extended investigation. Wider implications of the findings In TESE-ICSI, especially in the case of NOA, it is difficult to obtain good quality embryos due to poor ICSI outcomes. However, if good quality embryos are obtained, the euploidy rate is high and there is no need to perform PGT-A on the sole basis of using testicular sperm. Trial registration number not applicable