Association of Y Chromosome Microdeletions with Reproductive Profiles in 2010 Infertile Male Patients in China

To study the incidence of the chromosome abnormalities and Y chromosome microdeletions in Chinese patients with azoospermia and cryptozoospermia. Conventional chromosomal karyotyping was used to analyze the chromosome abnormalities. Genomic DNA was extracted from peripheral blood samples and multiplex polymerase chain reactions (PCR) analyses were performed using specific primers to confirm the presence or absence of Y chromosome microdeletions. A total of 997 patients with azoospermia and cryptozoospermia were enrolled in the study. The incidence of chromosome abnormalities in the patient with azoospermia and cryptozoospermia was 28.4%. The major abnormal karyotypes included 47,XXY, 46,XY (Y>G), 46,XX, chimera and translocations. The incidence of the Y chromosome microdeletions was 17.4%. They were mainly found in the karyotypes of 46,XY and 46,XY (Y>G). Chromosome abnormalities were the most common hereditary causes of the patients with azoospermia and cryptozoospermia. The incidence of Y chromosome microdeletion was higher in the patients with karyotype of 46,XY and 46,XY (Y>G). Therefore, detection of the AZF microdeletion in these patients is helpful to determine the etiology and avoid the unnecessary treatment and vertical transmission of the genetic defects.

Infertility is a disease of the reproductive system defined by the failure to achieve a clinical pregnancy after 12 months or more of regular unprotected sexual intercourse. Worldwide, infertility affects approximately 15% of all couples trying to conceive. Male infertility is responsible for about 50% of the infertility cases. Chromosomal abnormalities and Y-chromosome microdeletions are the most common genetic causes of male infertility. Klinefelter syndrome (KS) is the most prevalent factor of the chromosomal abnormality in the infertile male. Azoospermia Factor (AZF) microdeletions located on the Y chromosome are one of the recurrent genetic cause of male infertility. This study aims to investigate the prevalence of chromosomal anomalies and AZF microdeletions in 296 infertile Kurdish men in Erbil province, 289 patients diagnosed as azoospermia (97.6%) and 7 patients as severe oligozoospermia (2.4%) and 50 healthy men as control group. Twenty nine patients (9.8%) had various chromosomal abnormalities. The most common chromosomal abnormalities were found in sex chromosomes (93.1%; 29/27), among these abnormalities 20 patients (69%) had Klinefelter syndrome 47,XXY karyotype, 4 patients (13.8%) had 45X0/46, Xder(Y), 2 patients (6.9%) had XXY t(11;22)(q25;q13) and 1 patients (3.4%) had Mosaic Turner syndrome 46XY/45X0. The autosomal chromosomal abnormalities (6.9%; 2/29) detected in 2 patients 45, XY, rob (13;14) (q10;q10). Y chromosome microdeletions were found in 10 of 289 patients with azoospermia (3.5%), three of them (30%) had microdeletions in the AZFc region, 3 of them (30%) had microdeletions in the AZFb region, also other 3 patients had microdeletions in the b and c of AZF (AZF b,c) region, and the final one patient (10%) had microdeletions in the all a, b and c (AZF a,b,c) region. Combined Y chromosome microdeletions and chromosomal abnormalities were detected in 3 patients.

Y chromosome microdeletions (YCMs) are one kind of genetic disorder that contributes to male infertility. This study aims to determine the profile of YCMs in the infertile male population in Indonesia. This cross-sectional study was conducted by identifying YCMs testing data on 49 infertile male patients identified with azoospermia and oligoasthenoteratozoospermia (OAT) based on their sperm analysis, who visited andrology polyclinics in several hospitals in Yogyakarta Province between March 2021 to August 2022. Study participants underwent YCMs testing at the Molecular Medicine and Therapy Research Laboratory, Muhammadiyah University of Yogyakarta, Indonesia, using the Polymerase Chain Reaction (PCR) method according to the procedures established by the laboratory. Four out of 49 (8.2%) participants were identified to have YCMs with deletions in the Azoospermia Factor C (AZFc) subregion. Two participants identified with YCMs had cryptozoospermia in their sperm analysis. Hormonal examination showed variable results in 4 participants, including hypergonadotropic, hypogonadism, and normogonad. All participants in the study identified with YCMs showed a deletion in the AZFc subregion. This type of deletion is different from previous studies in Indonesia, so broad examinations of infertile male patients are required to figure out the deletion profile in a larger population of Indonesian sterile males.

In recent years, male infertility has shown a significant upward trend globally. Y chromosome microdeletions (YCMs), known as microdeletions within azoospermia factor (AZF), and chromosomal abnormalities are the leading genetic causes of male infertility. This study summarizes the detection of YCMs, karyotype results, and sex hormone levels in male infertility patients, with the aim of providing theoretical support for clinical diagnosis and treatment. A retrospective analysis was conducted on 3060 male infertility patients treated at the General Hospital of Ningxia Medical University between January 2016 and December 2024. Patients were classified according to semen parameters into azoospermia and oligozoospermia groups, and subgroup analyses were performed to compare the prevalence of YCMs and karyotypic abnormalities, as well as to assess hormonal differences between groups. The overall detection rate of YCMs in patients with infertility was 8.24%. AZFc deletions were most common (64.68%), followed by AZFb + c deletions (19.05%). YCMs were significantly more prevalent in azoospermia (12.70%) than in oligozoospermia (5.99%) (P < .001). AZFb + c deletions predominated in azoospermia (36.92%), whereas AZFc deletions were nearly exclusive in oligozoospermia (98.36%). The overall chromosomal karyotype abnormality rate was 8.01%, which was significantly higher in the azoospermia (15.72%) group than in the oligozoospermia (4.13%) group (P < .001). Patients with YCMs exhibited a significantly higher rate of abnormal karyotypes (40.48%) than those without YCMs (5.09%) (P < .001). Azoospermia patients had significantly higher luteinizing hormone and follicle-stimulating hormone levels and lower testosterone levels than oligozoospermia patients (all P < .001). Patients with YCMs had significantly higher luteinizing hormone and follicle-stimulating hormone levels than those without YCMs (P < .001 and P < .05) and the hormonal alterations associated with YCMs were independent of age. Genetic screening is conducive to identifying potential genetic disorders that may be associated with infertility, providing auxiliary support for the formulation of personalized treatment plans and the selection of appropriate assisted reproductive technologies.

The aim of this study was to study the incidence of Y chromosome microdeletions in a Caucasian population of Klinefelter syndrome (KS) patients and to investigate the possible association between Y chromosome microdeletions and KS. We conducted a retrospective study on 118 KS patients, 429 patients with non-obstructive azoospermia (NOA), and 155 normozoospermic men. Eight of the 118 KS patients had undergone testicular sperm extraction (TESE). All patients underwent semen examination and Y chromosome microdeletions evaluated by PCR, using specific sequence tagged site (STS) primer sets, which spanned the azoospermia factor AZFa, AZFb, and AZFc regions of the Y chromosome. Semen analysis of the KS group revealed: 1 patient with oligozoospermia, 1 with severe oligoasthenoteratozoospermia, 2 with cryptozoospermia, and 114 with azoospermia. Eight of the 114 azoospermic KS patients underwent TESE, and spermatozoa were recovered from three of these, all of whom had non-mosaic karyotype 47, XXY. 10.7% of the NOA patients presented AZF microdeletions. In 429 cases with NOA, 8 cases had AZFa + b+c deletion, 6 cases had AZF b + c deletion, 4 cases had AZFa microdeletion, 8 cases had AZFb microdeletion, and 20 cases had AZFc microdeletion. Just one KS patient (0.8%) presented microdeletion in the AZFc region. The percentage of microdeletions in KS patients was lower than in NOA patients, suggesting that AZF microdeletions and KS do not have a causal relationship and that Y chromosome microdeletions are not a genetic factor linked to KS.

Male Infertility and the Y Chromosome

Objective: To determine the frequency, types of chromosomal abnormalities and Y chromosome microdeletions in patients with severe male factor infertility, and the association between clinical background and genetic abnormality. Study design: A total of 322 infertile men; 136 men with severe oligozoospermia (sperm count <5 million/ml) and 196 with nonobstructive azoospermia were studied between April 2004 and November 2006 at the Dr. Zekai Tahir Burak Women’s Health Education and Research Hospital, Ankara, Turkey. Blood, semen samples, and testicular biopsies of patients were obtained. Hormonal analysis (follicle-stimulating hormone (FSH), luteinizing hormone (LH), and testosterone levels), semen analysis, karyotype analysis, and PCR screening for Y chromosome microdeletions were performed. Result(s): Forty-eight out of 332 (14%) infertile men had a genetic abnormality. Twenty-four (7.2%) cases with karyotype abnormality were detected. The frequencies of karyotype abnormalities were Klinefelter’s syndrome 17/24 (71%), translocation 3/24 (12%), mix gonadal dysgenesis 2/24 (8%), XX male 1/24 (4%), and 46XYY 1/24 (4%). Twenty cases (6%) infertile men had only Y chromosome microdeletions. The frequencies of the deleted areas were azoospermia factor (AZF)c 42%, AZFb 25%, AZFa 21%, AZFb, c 8%, and AZFa, c 4%. Four of the cases with Y chromosome microdeletions also had a concurrent karyotype abnormality. Conclusion(s): All patients with nonobstructive azoospermia and severe oligozoospermia (sperm count <5 million/ml) should undergo genetic screening.

Study question What is the frequency of azoospermia factor (AZF) microdeletions and sperm retrieval rate (SRR) by micro TESE in patients with these deletions? Summary answer AZFc is most frequent of Y chromosome microdeletions and a predictor of micro TESE outcome in Japanese azoospermic men. What is known already After Klinefelter syndrome, Y chromosome microdeletions are the second most frequent genetic cause of male infertility, with a prevalence of 2%-10% in non-obstructive azoospermia (NOA) and three spermatogenesis loci in the Y chromosome long arm (Yq11) have been classified as AZFa, AZFb, and AZFc. The classical correlation of histopathology phenotypes with these three microdeletions comprises of complete absence of germ cells (Sertoli cell-only syndrome) in patients with AZFa microdeletions, maturation arrest of meiosis in patients with AZFb microdeletions, and hypospermatogenesis in patients with AZFc microdeletions, however, individual variation in the extent of deletions has led to various spermatogenic phenotypes. Study design, size, duration We performed a retrospective study based on two reproduction centers in Japan and evaluated 1373 azoospermic patients in our clinics between September 2013 and December 2021. We investigated the frequency of AZF microdeletions and SRR by micro TESE in patients with these microdeletions and therefore aimed to evaluate the correlation between AZF microdeletions and micro TESE results. Participants/materials, setting, methods A total of 1373 azoospermic were enrolled. After the diagnosis of azoospermia, karyotype analysis and detection of Y chromosome microdeletions were performed on peripheral blood lymphocytes of these patients. Y chromosome microdeletions in AZFa, AZFb, and AZFc regions were detected using Promega Y Chromosome AZF Analysis System version 2.0 (Promega Co.). Twenty sequence-tagged sites within the AZF region of Yq11 and the sex-determining region Y gene were targeted for polymerase chain reaction (PCR) amplification. Main results and the role of chance One hundred and fifty-two AZF microdeletions (11.1%) were detected in the azoospermic patients. The most common deleted region was AZFc (60 cases, 4.4%). Among the patients, 17 (1.2%), 1 (0.1%), 42 (3.1%), 13 (1.0%), and 6 (0.5%) had AZFa, AZFa+b, AZFb+c, AZFb, and AZFa+b+c microdeletions, respectively. When the cases were grouped according to causes of infertility that could be detected, no Y chromosome microdeletions were detected in some groups (cases with Klinefelter Syndrome, hypogonadotropic hypogonadism, congenital absence of vas deferens, and 47, XYY karyotype). Fifty-three azoospermic men with AZFc microdeletions underwent micro TESE, and spermatozoa were detected in 88.7% (47/53) of these men. In contrast, we detected spermatozoa in only 20.4% (109/534) of the azoospermic men without AZF microdeletions. The SRR was much higher in patients with AZFc microdeletions than that of patients without AZF deletions. Although three azoospermic men with AZFb+c microdeletions had also undergone micro TESE following patient request, we did not retrieve spermatozoa. Limitations, reasons for caution We excluded post chemotherapy NOA showing 46, XX and AZFa+b+c deletions post bone marrow transplantation from female donor. Additionally, we did not detect AZFc partial deletion including gr/gr deletion. The cohort size of this study is not small, however, our screened population of infertile men may be biased. Wider implications of the findings NOA patients with AZFc microdeletions had a high percentage of successful sperm retrieval by micro TESE. Our study emphasizes that diagnosis of Y chromosome microdeletions is critical for preconception genetic counseling and provides clinically valuable prognostic information to couples considering surgical sperm retrieval. Trial registration number None

To explore the clinical significance of azoospermia factor (AZF) region deletion. Detection of the Y-link sequence tagged sites in AZF region was conducted by means of 2 multiplex polymerase chain reactions among 80 patients with severe oligozoospermia and 63 patients with azoospermia, totally 143. Twenty-one cases of microdeletion were found among the 143 infertile patients with a prevalence of 14.7%. PCR analysis showed that deletion of the portions of Yq in 12 of the 62 idiopathic infertility patients, 3 being with severe oligozoospermia and 9 with azoospermia, and in 9 out of the 81 patients with non-idiopathic infertility. PCR analysis of 40 normal fertile men did not detect any abnormality. The results of the microdeletion showed that 1 patient had a microdeletion in the AZFa region with sY84 and sY86 (1/21, 4.8%), 2 patients presented a large deletion involving sY127 and sY143 from AZFb, and sY254 and sY255 from AZFc (1/21, 9.5%). Two patients had the deletions located in AZFb region (2/21, 9.5%), and 16 patients had a deletion on the AZFc region involving the DAZ (deleted in azoospermia) gene (16/21, 76.2%) Among the 21 infertile men 4 showed a testicular cytologic picture of maturation arrest, 6 patients had severe hypospermatogenesis, and 11 had Sertoli cell-only syndrome. There were not significant differences in location and extent of deletions between the patients with idiopathic infertility and those with non-idiopathic infertility. It is recommended to carry out screening of microdeletion of Y chromosome among the patients with idiopathic and non-idiopathic infertility, especially the candidates for intracytoplasmic sperm injection.

Y chromosome micro-deletion (YCM) is a group of genetic diseases caused by missing gene (s) in specific regions of the Y chromosome. Many individuals with YCM show no manifestations and lead normal life. On the other hand, YCM is known to exist in a significant number of infertile males. Forty adult patients suffering from severe oligospermia and azoospermia were enrolled in the present study. Seminal fluid analyses were performed, and a blood sample was obtained for hormonal analysis and DNA extraction. Follicle stimulating hormone (FSH) and luteinizing hormone (LH) profiles were measured and those who are azoospermic with normal FSH levels were subjected to testicular biopsy. The results revealed that 23 patients were azoospermic while 17 patients were severe oligospermic. It is also shown that ten azoospermic patients had normal serum gonadotrophin levels thus they were directed for testicular biopsy. Histopathological examination of testicular biopsy showed that four patients had obstructive azoospermia while the remaining six suffered maturation arrest. DNA was extracted according to the standard proteinase K/phenol-chloroform method in the medical biotechnology laboratory/Scientific Research Center/University of Duhok. Multiplex PCR was performed for genes located in the azoospermia factor (AZF) regions (AZFa, AZFb, and AZFc) to detect any possible micro-deletions. Y chromosome micro-deletions were determined in 26 patients out of a total of 40 patients. Micro-deletions in the AZFc sub-region appeared in 16 out of 26 patients (61.5 %), and 10 (38.5 %) sample showed AZFb, however, AZFa micro-deletion was not detected in any of the patients. In conclusion, it has been found that Y chromosome micro-deletions in the AZF region can be a determining factor for male infertility and the resultant manifestations.

BackgroundThe incidence of Y chromosome microdeletions varies among men with infertility across regions and ethnicities worldwide. However, comprehensive epidemiological studies on Y chromosome microdeletions in Chinese men with infertility are lacking. We aimed to investigate Y chromosome microdeletions prevalence among Chinese men with infertility and its correlation with intracytoplasmic sperm injection (ICSI) outcomes.MethodsThis single-center retrospective study included 4,714 men with infertility who were evaluated at the Reproductive Center of the First Affiliated Hospital of Sun Yat-sen University between May 2017 and January 2021. Semen analysis and Y-chromosome microdeletion via multiplex polymerase chain reaction were conducted on the men. The study compared outcomes of 36 ICSI cycles from couples with male azoospermia factor (AZF)cd deletions with those of a control group, which included 72 ICSI cycles from couples without male Y chromosome microdeletions, during the same period. Both groups underwent ICSI treatment using ejaculated sperm.ResultsAmong 4,714 Chinese men with infertility, 3.31% had Y chromosome microdeletions. The combined deletion of sY254 and sY255 in the AZFc region and sY152 in the AZFd region was the prevalent pattern of Y chromosome microdeletion, with 3.05% detection rate. The detection rates of AZF deletions in patients with normal total sperm count, mild oligozoospermia, severe oligozoospermia, cryptozoospermia, and azoospermia were 0.17%, 1.13%, 5.53%, 71.43%, and 7.54%, respectively. Compared with the control group, the AZFcd deletion group exhibited no significant difference in the laboratory results or pregnancy outcomes of ICSI cycles using ejaculated sperm.ConclusionsThis is the largest epidemiological study on Y chromosome microdeletions in Chinese men with infertility. The study results underline the necessity for detecting Y chromosome microdeletion in men with infertility and severe sperm count abnormalities, especially those with cryptozoospermia. The combined deletion of sY254 and sY255 in the AZFc region and sY152 in the AZFd region was the most prevalent Y chromosome microdeletion pattern. Among patients with AZFcd deletion and ejaculated sperm, ICSI treatment can result in pregnancy outcomes, similar to those without AZFcd deletion.

The major genetic causes in male infertility are chromosomal abnormalities and Y chromosomal microdeletions (YCMs). YCMs occur in approximately 15% of azoospermic patients and 10% of severe oligospermic patients. These microdeletions lead to spermatogenic failure.

PurposeDespite all past efforts, the current guidelines are not explicit enough regarding the indications for performing azoospermia factor (AZF) screening and karyotype, burdening clinicians with the decision to assess whether such tests are meaningful for the infertile male patient. These assessments can be costly and it is up to the healthcare practitioner to decide which are necessary and to weigh the benefits against economic/psychological harm. The aim of this study is to address such gaps and provide update on current management options for this group of patients.Materials and MethodsTo address such gaps in male infertility management and to elucidate whether AZF screening is indicated in individuals who concomitantly harbor chromosomal abnormalities we conducted a retrospective cohort analysis of 10,388 consecutive patients with non-obstructive azoospermia (NOA) and severe oligozoospermia.ResultsPreviously, it has been suggested that all NOA cases with chromosomal defects, except males with 46,XY/45,X karyotype, have no indication for AZF screening. Our findings revealed that cases carrying the following chromosomal abnormalities inv(Y)(p11.2q12); idic(Y)(q11.2); 46,XY,r(Y); idic(Y)(p11.2) and der(Y;Autosome) (76/169; 44.9%; 95% CI, 37.7–52.5) should also be referred for AZF deletion screening. Here, we also report the correlation between sperm count and AZF deletions as a secondary outcome. In accordance with previously reported data from North America and Europe, our data revealed that only 1% of cases with >1×106 sperm/mL had Y chromosome microdeletions (YCMs).ConclusionsIn the era of assisted reproduction, finding cost-minimization strategies in infertility clinics without affecting the quality of diagnosis is becoming one of the top prioritized topics for future research. From a diagnostic viewpoint, the results reflect a need to reconsider the different karyotype presentations and the sperm count thresholds in male infertility guidelines as indicators for YCM screening during an infertility evaluation.

Introduction Male-factor infertility contributes to a substantial portion of infertility cases. Genetic factors are believed to play an important role, with Y chromosome microdeletions commonly identified among men with azoospermia. Due to the relatively high prevalence of these deletions, genetic testing for Y chromosome microdeletions has become a routine component of the diagnostic workup for infertile men. While deletions in the AZF (Azoospermia Factor) region are known to impair spermatogenesis, the hormonal profile in this population remains poorly characterized. Hormonal evaluation plays a key role in guiding treatment decisions, including the use of empirical medical therapy (EMT). However, there is limited data on hormonal profiles and EMT usage in men with AZF deletions. Objective We aimed to characterize preoperative hormonal profiles and evaluate the use and outcomes of EMT in men with AZF microdeletions undergoing surgical sperm retrieval. Methods We conducted a multi-institutional retrospective cohort study of men with genetically confirmed AZF micro-deletions, including AZFa, AZFb, AZFc, and combined deletions. Data were collected on preoperative serum gonadotropin levels (follicle-stimulating hormone [FSH] and luteinizing hormone [LH]), total testosterone (TT), and semen analysis parameters. Additionally, we evaluated patterns of empirical medical therapy (EMT) prescriptions and outcomes of surgical sperm retrieval. Results 40 men with confirmed Y-chromosomal micro-deletions across three academic centers was identified. Patients with SRY translocations (n=4) were excluded from the study. The final cohort included 27 patients with AZFc deletions (75%), 2 with AZFa (6%), 1 with AZFb (3%), and 6 with multilocus deletions (17%). FSH (reference: &amp;gt;7.6 mIU/mL) was elevated in 23 patients (64%), with a median of 19.6 IU/L (IQR: 14.4–25.8). LH (reference: &amp;gt;9 mIU/mL) was elevated in 8 patients (22%), with a median of 14.9 IU/L (IQR: 13.7–20.1). Overall median TT was 243.5 (7.7-379.7). TT was below the lower limit of normal (&amp;lt;300 ng/dL) in 13 patients (36%), with a median of 184 ng/dL (IQR: 133–233). Most patients were azoospermic on semen analysis (86%, n=31/36). Of the seven men treated with EMT, the majority (6/7, 86%) received clomiphene citrate. While there were differences in initial levels of TT, FSH, and LH for those treated with EMT compared to those without EMT, these were not statistically significant (Table 1). Among the 13 patients who underwent surgical sperm retrieval, 6 (46%) had successful outcomes; however, only one had received EMT. Conclusions Men with AZF deletions exhibit varying degrees of hormonal imbalance and rates of empirical medical therapy (EMT) use. Despite EMT, sperm retrieval outcomes were poor, with only 1 out of 7 EMT-treated patients achieving successful sperm retrieval. While hormonal differences were observed between those who received EMT and those who did not, these differences did not reach statistical significance. This is likely due to the limited sample size inherent to this rare patient population. Our findings underscore the variability in hormonal profiles and the unclear efficacy of EMT in promoting spermatogenesis in men with AZF deletions, highlighting the need for further research to inform standardized management strategies. Disclosure No

The microdeletions of azoospermia factor (AZF) genes in Y chromosome are greatly associated with male infertility, which is also known as the second major genetic cause of spermatogenetic failure. Accumulating studies demonstrate that the different type of AZF microdeletions in patients reflect different clinical manifestations. Therefore, a better understanding of Y chromosome microdeletions might have broad implication for men health. In this study, we sought to determine the frequency and the character of different Y chromosome microdeletion types in infertile men in southwest of China.In total, 1274 patients with azoospermia and oligozoospermia were recruited in southwest of China and screening for Y chromosome microdeletions in AZF regions by multiplex polymerase chain reaction.The incidence of AZF microdeletions in southwest of China is 12.87%, which is higher than the national average. Further investigations unveiled that azoospermia factor c (AZFc) is the most frequent type of all the AZF microdeletions. Additionally, the number and also the quality of sperm in patients with AZFc microdeletion is decreasing with the age. Therefore, it is conceivable that the early testing for Y chromosome microdeletions in infertile men is crucial for fertility guidance.The early detection of Y chromosome microdeletions in infertile men can not only clearly explain the etiology of oligzoospermia and azoospermia, but also help for the clinical management of both infertile man and his future male offspring.