Bilateral Absence Of Vas Deferens Research Articles

CFTR Exon 10 deleterious mutations in patients with congenital bilateral absence of vas deferens in a cohort of Pakistani patients.

Congenital bilateral absence of vas deferens (CBAVD) is a urological syndrome of Wolffian ducts and is responsible for male infertility and obstructive azoospermia. This study is designed to explore the integrity of exon 10 of CFTR and its role in male infertility in a cohort of CBVAD patients in Pakistan. Genomic DNA was extracted from 17 male patients with CBAVD having clinical symptoms, and 10 healthy controls via phenol-chloroform method. Exon 10 of the CFTR gene was amplified, using PCR with specific primers and DNA screening was done by Sanger sequencing. Sequencing results were analyzed using freeware Serial Cloner, SnapGene, BioEdit and FinchTV. Furthermore, bioinformatics tools were used to analyze the mutations and their impact on the protein function and stability. We have identified 4 mutations on exon 10 of CFTR in 6 out of 17 patients. Two of the mutations were missense variants V456A, K464E, and the other two were silent mutations G437G, S431S. The identified variant V456A was present in 4 of the studied patients. Whereas, the presence of K464E in our patients further weighs on the crucial importance for its strategic location to influence the gene function at post-transcriptional and protein level. Furthermore, Polyphen-2 and SIFT analyze the mutations as harmful and deleterious. The recurrence of V456A and tactically conserved locality of K464E are evidence of their potential role in CBAVD patients and in male infertility. The data can contribute in developing genetic testing and treatment of CBAVD.

The role of the radiologist in the evaluation of male infertility: recommendations of the European Society of Urogenital Radiology-Scrotal and Penile Imaging Working Group (ESUR-SPIWG) for scrotal imaging.

The Scrotal and Penile Imaging Working Group (SPIWG) of the European Society of Urogenital Radiology (ESUR) aimed to produce recommendations on the role of the radiologist in the evaluation of male infertility focused on scrotal imaging. The authors independently performed an extensive literature Medline search and a review of the clinical practice and consensus opinion of experts in the field. Scrotal ultrasound (US) is useful in investigating male infertility. US abnormalities related to abnormal sperm parameters (sperm concentration, total count, motility, and morphology) are low testicular volume (TV), testicular inhomogeneity (TI), cryptorchidism, testicular microlithiasis (TML), high-grade varicocele, bilateral absence of vas deferens, bilateral dilation and echotexture abnormalities of the epididymis. The proposed ESUR-SPIWG recommendations for imaging in the evaluation of male infertility are therefore: to measure TV; investigate TI; perform annual (US) follow-ups up to age 55 in men with a history of cryptorchidism/orchidopexy and/or in men with TML plus "additional risk factors" or with "starry sky" TML; perform scrotal/inguinal US in men with nonpalpable testis; perform scrotal US in men with abnormal sperm parameters to investigate lesions suggestive of tumors; evaluate varicocele in a standardized way; evaluate the presence or absence of vas deferens; investigate the epididymis to detect indirect signs suggesting obstruction and/or inflammation. The ESUR-SPIWG recommends investigating infertile men with scrotal US focusing on TV, inhomogeneity, localization, varicocele, vas deferens, and epididymal abnormalities. Cryptorchidism, TML, and lesions should be detected in relation to the risk of testicular tumors. The ESUR-SPIWG recommendations on scrotal imaging in the assessment of male infertility are useful to standardize the US examination, focus on US abnormalities most associated with abnormal semen parameters in an evidence-based manner, and provide a standardized report to patients. So far, ESUR-SPIWG recommendations on scrotal imaging in the assessment of male infertility were not available. The ESUR-SPIWG recommends investigating infertile men with scrotal US focusing on testicular volume, inhomogeneity, localization, varicocele, vas deferens and epididymal abnormalities, and assessing cryptorchidism, testicular microlithiasis and lesions in relation to the risk of testicular tumors. The ESUR-SPIWG recommendations on scrotal imaging in the assessment of male infertility are useful to standardize the US examination, focus on US abnormalities most associated with abnormal sperm parameters in an evidence-based manner, and provide a standardized report to patients.

Compound heterozygous variants in CFTR with potentially reducing ATP-binding ability identified in Chinese infertile brothers with isolated congenital bilateral absence of vas deferens.

Isolated congenital bilateral absence of vas deferens (iCBAVD) in men results in obstructive azoospermia and is mainly caused by pathogenic variants in cystic fibrosis transmembrane conductance regulator (CFTR) or adhesion G protein-coupled receptor G2 (ADGRG2). The next-generation sequencing (NGS) was used to screen the mutations in the proband, and Sanger sequencings were performed to validate the compound heterozygous variant of CFTR in his family members. Protein structure simulation was performed to discover the potential pathological mechanism. This study reported novel compound heterozygous CFTR mutations (NM:000492.4, Intron: 5T; c.3965_3969dupTTGGG: p.R1325Gfs*5) in two brothers with obstructive azoospermia. The compound heterozygous CFTR mutations were first screened out by NGS in an infertile male patient who exhibited iCBAVD from a nonconsanguineous Chinese family. Histological analysis of the testicular biopsy from this patient revealed normal spermatogenesis and mature spermatozoa were observed in the seminiferous tubules. Surprisingly, the same compound heterozygous CFTR mutations were also observed in his brothers who also exhibited iCBAVD, with their parents being a heterozygous carrier for the mutations, as verified by Sanger sequencing. Protein structure simulation revealed that these mutations potentially led to impaired ATP-binding ability of CFTR. We identified novel compound heterozygous CFTR mutations in two brothers and summarized the literature regarding CFTR mutation and male infertility. Our study may contribute to the genetic diagnosis of iCBAVD and future genetic counseling.

P-554 Impact of genotype and phenotype on ICSI outcomes of cystic fibrosis (CF) men patients: a cohort study about 107 ICSI from 1999 to 2019

Abstract Study question Is there an impact of CFTR (cystic fibrosis transmembrane-conductance regulator) gene mutation type and/or general health condition of men with CF and the ICSI outcomes? Summary answer Neither genetic severity nor clinical severity seems to have a negative impact on the biological or clinical ICSI issues for cystic fibrosis men patients. What is known already CFTR protein regulates electrolyte and fluid transport in many tissues with exocrine function, including male reproductive tract. Mutation of CFTR gene causes CF, which affects the function of several organs, and impairs male fertility. CF is generally associated to an obstructive azoospermia because of bilateral absence of vas deferens and seminal vesicles degeneration. CFTR protein is detected in human fetus at the early developmental stages and highly expressed in testis and epididymis. CFTR provides establishment of specific fluid environment for germ cell differentiation and maturation. According to literature, it seems likely that CFTR mutations affect sperm quality and embryo development. Study design, size, duration This cohort study was conducted in the Assisted Reproduction Center of an university hospital on 52 patients, for whom a CF has been diagnosed and monitored in the same hospital. The CF diagnosis was based on CFTR genetic tests and clinical symptoms. All men were azoospermic and underwent on a microscopic epididymal sperm aspiration (MESA) and/or a testicular sperm extraction (TESE). 52 couples underwent in total 107 ICSI with frozen sperm between 1999 and 2019. Participants/materials, setting, methods Clinical data- one year preceding surgical sperm collection and freeze - related to the severity of the CF were collected: respiratory spirometry data, Pseudomonas aeruginosa colonization, number of antibiotic treatment, BMI and Pancreatic insufficiency, as well as CFTR mutations. Linear regression tests (fisher and χ²) were carried out to establish or not correlation between biological and clinical ICSI outcomes and on the other hand genotype and/ or each clinical parameter. Main results and the role of chance The mean age of patients at sperm retrieval was 31.3 years [21-55]. Mean BMI was 21.3. Patients with severe genotype represented 67.8% and likely (67.3%) with external pancreatic deficiency. P.aeroginosa colonization was revealed in 30% of cases and 45.6% patients received at least one IV antibiotic treatment. Respiratory function has been impaired in 18 cases, with a maximal expiratory volume per second < 40%. Spermatozoa were found and frozen for all patients after surgical sperm retrieval (20 MESA and 32 MESA + TESE). The mean number of epididymal motile progressive spermatozoa was satisfactory (10.2±18.83 million). Women mean age was 30 years at ICSI and female infertility was associated in 15.4%. Fertilization and cleavage rates were 66% both. Mean number of transferred and/or frozen embryos per attempt was 3. Implantation rate was 20%. A total of 50 pregnancies and 44 live births were obtained (35.5% of cumulative clinical pregnancy rate per ICSI and 29.1% of live birth rate per transfer). Fertilization rate, absence of pregnancy or absence of live birth were not affected by the genetic severity (p = 0.63, p = 0.46 and p = 0.16 respectively). Likewise, and after several univariate analyses there was no statistically significant correlation between clinical severity and ICSI outcomes. Limitations, reasons for caution Practices of assisted reproduction have constantly evolved during the study period, this concerns the controlled ovarian stimulation protocols, IVF techniques, equipment and culture media used. Our study needs to be completed by a multivariate analyse Wider implications of the findings Regarding to better quality of life of CF patients nowadays and to our results- with no significant correlation between genetic and/or clinical severity and ICSI outcomes, surgical sperm collection can be proposed only in case of a conceptional project or before transplantation and immunosuppressive agents in order to perform ICSI. Trial registration number for non-clinical trials

Cystic Fibrosis assessment in infertile couples: genetic analysis trough the Next Generation Sequencing technique

Background: Cystic Fibrosis (CF) is a genetic disease which is responsible for different systemic conditions. In particular, CF could be responsible for infertility, especially in the male partner due to congenital bilateral absence of vas deferens (CBAVD). Moreover, in Assisted Reproductive Techniques CF screening is performed in order to detect possible risks for the newborn. For this reason, CF testing is one of the main genetic screening performed in infertile couples. Methods: In this scenario, we present a prospective observational study in CF testing with Next Generation Sequencing (NGS) technique on 360 subjects referring to an In-Vitro Fertilization center. Results: 360 subjects were screened for CFTR. Of them, 19 subjects presented CF causing variants, 44 subjects presented CFTR-RD associated, 22 subjects had variants of uncertain significance and 19 subjects with no clinical consequences. Conclusion: Results clarify proportions of the main CF mutations. Actually, there are no more advanced techniques rather than Next Generation Sequencing (NGS) technique, although it is not yet widely used as a test for the identification of the CF carrier.

Genetic analysis and intracytoplasmic sperm injection outcomes of Chinese patients with congenital bilateral absence of vas deferens.

Congenital bilateral absence of the vas deferens (CBAVD) is a major cause of obstructive azoospermia and male factor infertility. CBAVD is mainly caused by mutations in the genes encoding CFTR (cystic fibrosis transmembrane conductance regulator) and ADGRG2 (adhesion G protein-coupled receptor G2). This study aimed to describe CFTR and ADGRG2 variations in 46 Chinese CBAVD patients and evaluated sperm retrieval and assisted reproductive technology outcomes. The CFTR and ADGRG2 genes were sequenced and analyzed by whole-exome sequencing (WES), and variations were identified by Sanger sequencing. Bioinformatic analysis was performed. We retrospectively reviewed the outcomes of patients undergoing sperm retrieval surgery and intracytoplasmic sperm injection (ICSI). In total, 35 of 46 (76.09%) patients carried at least one variation in CFTR, but no copy number variants or ADGRG2 variations were found. In addition to the IVS9-5T allele, there were 27 CFTR variations, of which 4 variations were novel and predicted to be damaging by bioinformatics. Spermatozoa were successfully retrachieved in 46 patients, and 39 of the patients had their own offspring through ICSI. There are no obvious hotspot CFTR mutations in Chinese CBAVD patients besides the IVS9-5T allele. Therefore, WES might be the best detection method, and genetic counseling should be different from that provided to Caucasian populations. After proper counseling, all patients can undergo sperm retrieval from their epididymis or testis, and most of them can have their own children through ICSI.

Unilateral Kidney Agenesis and other Kidney Anomalies in Infertile Men with Congenital Bilateral Absence of Vas deferens: A Cross-Sectional Study.

Background:We aim to determine the prevalence of renal anomalies in patients with congenital vas deferens agenesis referred for infertility assessment.Materials and Methods:This cross-sectional study was carried out on eligible infertile men from 2016 to 2019. Infertile men who were suspected of obstructive azoospermia were referred to the Ultrasound ward and they were examined by abdominal ultrasound for detecting the genital and kidney anomalies. An informed consent form was filled out by patients. Data was entered into SPSS software 21. Patients were divided into two groups in terms of congenital bilateral absence of vas deferens (CBAVD) or congenital unilateral absence of the vas deferens (CUAVD). Using the Chi-square test kidney anomalies between groups were compared. The P<0.05 was considered significant.Results:The mean age of participants was 33.05 ± 6.35. The frequency of CBAVD was 66 and the frequency of left side VD and right side VD were 23 and 21, respectively. The percentage of other comorbidities was calculated. Out of 110 cases, 12 (11%) men had coexistence of vas deferens and kidney agenesis. Other studies are in agreement with our findings. Although the percentage of CBAVD and CUAVD were 9.1% and 1.8% respectively, the difference was not significant (P=0.07).Conclusion:Considering the fact that kidney agenesis is a remarkable congenital anomaly that coexists with the majority of vas deferens agenesis cases and could not be detected by routine laboratory tests or transrectal ultrasound examination, it should be ruled out with transabdominal ultrasound examination after detection of vas deferens agenesis.

Genetics of Azoospermia

Azoospermia affects 1% of men, and it can be due to: (i) hypothalamic-pituitary dysfunction, (ii) primary quantitative spermatogenic disturbances, (iii) urogenital duct obstruction. Known genetic factors contribute to all these categories, and genetic testing is part of the routine diagnostic workup of azoospermic men. The diagnostic yield of genetic tests in azoospermia is different in the different etiological categories, with the highest in Congenital Bilateral Absence of Vas Deferens (90%) and the lowest in Non-Obstructive Azoospermia (NOA) due to primary testicular failure (~30%). Whole-Exome Sequencing allowed the discovery of an increasing number of monogenic defects of NOA with a current list of 38 candidate genes. These genes are of potential clinical relevance for future gene panel-based screening. We classified these genes according to the associated-testicular histology underlying the NOA phenotype. The validation and the discovery of novel NOA genes will radically improve patient management. Interestingly, approximately 37% of candidate genes are shared in human male and female gonadal failure, implying that genetic counselling should be extended also to female family members of NOA patients.

Investigation of racial disparities in semen parameters among white, black, and Asian men

Male factor infertility is the primary cause of infertility in 20% of couples. Primary evaluation of male factor infertility includes a semen analysis (SA). The World Health Organization (WHO) criteria are widely used to interpret SA. However, the current normative values seen in WHO criteria have led to research showing racial disparities in prevalence of abnormal SA. To assess the relationship between different self-reported racial groups and rates of abnormal SA. We conducted a retrospective cohort study at a single large tertiary care facility. All men who underwent a SA for evaluation of suspected male infertility, unexplained infertility, intrauterine insemination, and in vitro fertilization between January 1, 2017 and December 31, 2019, were considered for inclusion in the study. Exclusion criteria were unreported race or ethnicity, SA for fertility preservation only, history of varicocele or testicular surgery, chromosomal abnormalities, congenital bilateral absence of vas deferens, prior testosterone use, or prior exposure to chemotherapy and/or radiation. Samples obtained via testicular sperm extraction or post-ejaculatory urine collection, or those analyzed ≥1 h from ejaculation, were also excluded. 872 SAs were identified, of which 615 met inclusion criteria, yielding 384 normal and 231 abnormal results. Only race (p<0.0001) and age (p=0.002) were statistically significant. Black men had the highest rate of abnormal SA (54%) and were significantly more likely to have lower semen volume, sperm concentration, total sperm count, percent motile sperm, and total motile sperm (p<0.05). In a logistic regression model, controlling for age and using White Non-Hispanic as the referent group, only Blacks had lower odds for a normal SA (OR=0.41, 95% CI 0.28, 0.60). Black men are more likely to have an abnormal SA based on the 2010 WHO criteria. Black men seeking infertility treatment should be educated on the incidence of abnormal SA and actively seek infertility evaluation.

Bilateral absence of vas deferens (BAVD) a case report

Mutations in transmembrane conductance of cystic fibrosis (CFTR) are found in men in couples followed for infertility and for which azoospermia associated with congenital bilateral absence of the deferential canal (CBAVD) were found in men. There is a frequent association between CFTR and CBAVD abnormalities. CBAVD exists in almost all men with cystic fibrosis and causes an obstructive azoospermia that cannot be treated surgically; this poses a diagnostic and therapeutic problem because its management remains complex. However, with the use of assisted reproductive techniques (ART), in particular the aspiration of testicular or epididymic sperm, the injection of intracytoplasmic sperm and in vitro fertilization, it is possible that men with CBAVD can produce offspring. We report the case of a 32-year-old patient who consulted for primary infertility evolving over the past 5 years (genetic advice was provided). The aim of this article is to show the diagnostic and therapeutic difficulties related to this particular form of male primary infertility. Recent assisted human reproduction techniques like Intracytoplasmic Sperm Injection (ICSI) or In Vitro Fertilization (FIV) offer very good results for couple consulting for infertility of man with CBAVD.

Prevalence of CBAVD in azoospermic men carrying pathogenic CFTR mutations - Evaluated in a cohort of 639 non-vasectomized azoospermic men.

BackgroundMen with obstructive azoospermia (OA) due to impaired development of the genital tract often carry at least one Cystic Fibrosis Transmembrane Conductance Regulator CFTR mutation.ObjectiveTo determine the frequency of Congenital Bilateral Absence of Vas deferens (CBAVD) in men with azoospermia carrying CFTR gene mutations.Materials and methodsNon‐vasectomized men with azoospermia referred to our andrological center were consecutively included. All men underwent palpation of the scrotal parts of the Vasa deferentia, ultrasonography of the testicles and hormone profile, and genetic analyses. Testicular biopsy was usually performed. A panel of 32 of the most important CFTR mutations was examined from genomic DNA isolated from blood lymphocytes. Either multiplex PCR analysis or a next‐generation sequencing technique was performed.ResultsAmong the 639 men with azoospermia, 69 (10.8%) had at least one CFTR mutation. Of the 43 patients with at least one of the two CFTR mutations, ΔF508 and R117H, 19 (44.2%) showed CBAVD, 2 (4.7%) Congenital Unilateral Absence of Vas deferens (CUAVD), and 22 (51.2%) presence of the scrotal parts of the Vasa deferentia. In contrast, only 1/21 men (4.8%) with an isolated IVS8‐5T variant showed CBAVD. Among the further 20 men with an isolated IVS8‐5T variant, 11 had a history of cryptorchidism. Among the 570 men without CFTR mutations, CBAVD was found in only two men and CUAVD in one. FSH level was higher and testicular volume lower in men with present Vasa deferentia compared to those without (P < .001; Student's t test). Thirty‐one men with either ΔF508 or R117H mutations, or both, had a testicular biopsy. Motile spermatozoa were found in 100% of 16 cases with CBAVD but in only 6 out of 15 cases with present Vasa deferentia (P < .01; Fisher's exact test).Discussion and conclusionsCBAVD was found in ~ 44% of men with ΔF508/R117H mutations. The data may support that CFTR mutations might affect male fertility through other mechanisms than obstruction of the genital tract. For a practical, clinical purpose analysis for only ΔF508, R117H and IVS8‐5T seems sufficient until further research shows anything else.

Cystic Fibrosis or Not? Familial Occurrence of a Rare Mutation in the CFTR Gene

Cystic fibrosis is a monogenic disease caused by a mutation in the CFTR gene. The classic presentation of the disease includes chronic bronchopulmonary symptoms. However, abnormalities in this gene may also be manifested by other phenotypes, so-called CFTR-related disorders. This is a group of entities including disseminated bronchiectasis, congenital bilateral absence of vas deferens, and chronic pancreatitis. In this article, we present a family with a rare F1052V mutation and a polymorphic variant of IVS-5T+11TG. No classical form of the disease was observed in any of the persons affected by the above changes. Results of special investigations are also not typical, which hinders unequivocal diagnosis.

Epididymal Appearance in Congenital Absence of Vas Deferens.

Scrotal sonography was performed in the infertile males. Sonography of epididymis was performed to document its presence, appearance, echo texture and duct ectasia. The spermatic cord was examined to document the status of the vas deferens. TRUS was performed to look for distal vas. Epididymal abnormalities were universal in men with congenital bilateral absence of vas deferens, with a sensitivity of 100%. Three types of abnormal appearances were recognized - a honeycomb appearance, a fine meshwork pattern of head, or complete or partial absence of epididymis. Identification of these abnormalities can be a very sensitive marker for congenital bilateral absence of vas deferens.

Analysis of CNVs of CFTR gene in Chinese Han population with CBAVD

BackgroundCongenital bilateral absence of vas deferens (CBAVD) is an important disease of male infertility, which affects 1%–2% of infertile population. In addition to common mutations of CFTR, copy number variants (CNVs) have also been implicated as one of the pathogenesis of CBAVD. The present study aimed to investigate the genetic contribution of CFTR CNVs in Chinese Han population with CBAVD.MethodsTwo hundred and sixty‐three CBAVD patients were recruited. Genomic DNA was extracted from peripheral blood samples. The Multiplex Ligation‐dependent Probe Amplification assay was performed which targets the region of the CFTR gene.ResultsAmong 263 Chinese men affected with CBAVD in this study, 5 (1.90%) patients were detected for copy number variants in the region of CFTR gene (4 of them carried partial deletions and 1 of them carried partial duplication of CFTR gene).ConclusionsThe study showed that the rate of CFTR CNVs in Chinese population with CBAVD were basically consistent with the previous reports. And the study first revealed genetic risk of CNVs of CFTR on a large sample size of CBAVD patients in Chinese Han population, which prompted that it was necessary to detect CNVs of CFTR in Chinese Han people with CBAVD.

A case of testicular atrophy associated with cystic fibrosis.

SummaryAn 8-year-old boy with cystic fibrosis came to our attention for an empty scrotum. General physical examination showed a normal penis and hypoplastic scrotum with non-palpable testes bilaterally. Routine blood investigations showed low levels of LH, testosterone, inhibin B and antiMullerian hormone and elevated levels of FSH. Karyotype was normal. An abdominal ultrasound confirmed the absence of the testes into the scrotum, in the inguinal region and abdomen. At laparoscopy were noted bilaterally hypotrophic spermatic vessels, absence of the vas deferens and a closed inner ring. Inguinal exploration found out a small residual testis and histological examination showed fibrotic tissue. This is the first case of testicular atrophy associated to CFTR mutation described. The process that led to bilateral testicular and vas deferens atrophy remains unexplained, a possible influence of CFTR dysfunction cannot be ruled out, although it is possible that these conditions are independently associated.Learning points:Cystic fibrosis produces a multisystemic disease which can affect also the reproductive tract.Nearly 97–98% of male patients are infertile because of congenital bilateral absence of vas deferens.A correlation between cystic fibrosis and bilateral testicular atrophy could be possible.

Genetic disorders and male infertility.

BackgroundAt present, one out of six couples is infertile, and in 50% of cases, infertility is attributed to male infertility factors. Genetic abnormalities are found in 10%‐20% of patients showing severe spermatogenesis disorders, including non‐obstructive azoospermia.MethodsLiteratures covering the relationship between male infertility and genetic disorders or chromosomal abnormalities were studied and summarized.Main findings (Results)Genetic disorders, including Klinefelter syndrome, balanced reciprocal translocation, Robertsonian translocation, structural abnormalities in Y chromosome, XX male, azoospermic factor (AZF) deletions, and congenital bilateral absence of vas deferens were summarized and discussed from a practical point of view. Among them, understanding on AZF deletions significantly changed owing to advanced elucidation of their pathogenesis. Due to its technical progress, AZF deletion test can reveal their delicate variations and predict the condition of spermatogenesis. Thirty‐nine candidate genes possibly responsible for azoospermia have been identified in the last 10 years owing to the advances in genome sequencing technologies.ConclusionGenetic testing for chromosomes and AZF deletions should be examined in cases of severe oligozoospermia and azoospermia. Genetic counseling should be offered before and after genetic testing.

Genetic diagnosis and sperm retrieval outcomes for Chinese patients with congenital bilateral absence of vas deferens.

Congenital bilateral absence of the vas deferens (CBAVD) is a frequent cause of obstructive azoospermia. CBAVD is mainly caused by mutations in the CFTR (cystic fibrosis transmembrane conductance regulator) gene and is also related to the X-linked ADGRG2 (adhesion G protein-coupled receptor G2) gene. Genetic screening and counseling strategies for Chinese CBAVD populations remain controversial because the genetic background of CBAVD in Chinese population is largely unknown. In this study, we aimed to study the mutation spectrum of CFTR and ADGRG2 in a group of CBAVD patients and to evaluate sperm retrieval outcomes in a subset of CBAVD patients. Next-generation targeted sequencing was used to identify mutations in the CFTR and ADGRG2 genes in 38 CBAVD patients. In addition, we followed and analyzed nine of the 38 patients who were undergoing sperm retrieval surgery. In total, 27 of 38 (71.05%) patients carried at least one likely pathogenic or pathogenic mutation in CFTR or ADGRG2. In addition to the IVS9-5T allele, 15 CFTR and 1 ADGRG2 mutations were identified, including 4 novel mutations. CFTR hot-spot mutations were not identified in our study. Spermatozoon was successfully obtained in all nine patients who underwent MESA or TESE surgery, but most patients had spermatozoa with relatively low motility and high abnormality rates. Except for the IVS9-5T allele, hot-spot mutations of CFTR may not exist in Chinese CBAVD patients. Therefore, next-generation targeted sequencing for whole CFTR and ADGRG2 gene may be the appropriate genetic testing method, and genetic counseling may be different from Caucasian populations. We observed a high success rate of sperm retrieval with relatively low motility and high abnormality rates in Chinese CBAVD patients. However, this is only a weak conclusion due to the small sample size.

Cystic fibrosis transmembrane conductance regulator-related male infertility: Relevance of genetic testing & counselling in Indian population.

Background & objectives:Due to limited information available on the frequency and spectrum of cystic fibrosis (CF) transmembrane conductance regulator (CFTR) gene mutations in congenital bilateral absence of vas deferens (CBAVD) in Indian population, it is difficult to provide accurate genetic counselling to couples. The present study was undertaken to investigate the spectrum and frequency of CFTR gene mutations in Indian men with CBAVD and to determine the female CF carrier status.Methods:Direct DNA sequencing of the CFTR gene was carried out in eighty CBAVD men, their female partners and fifty controls from the general population. Pathological significance of the identified novel CFTR gene variants was carried out using in silico tools. Appropriate genetic counselling was provided to the couples prior to intracytoplasmic sperm injection (ICSI).Results:A significant association was observed for CFTR gene variants in Indian CBAVD men versus controls (odds ratio: 12.1; 95% confidence interval: 4.8-30.4; P<0.0001). A total of 20 CFTR gene variants were identified in 53 CBAVD men. Eight novel missense CFTR gene variants (L214V, A238P, E379V, L578I, F587L, L926W, R1325K and R1453Q); two novel splice-site gene variants (c.1-30C>G and IVS1+2T>G) and ten previously reported mutations (R75Q, c.1210-12[5], F508del, A309G, R334W, I444T, R668C, R709X, A1285V and Q1352H) were detected in CBAVD men. The novel and reported CFTR gene mutations were L926W (2.5%, P=0.26), R1453Q (2.5%, P=0.26), F508del (8.75%, P=0.03) and c.1210-12[5] (42.5%, P=0.002). A total of 13 (16.2%) female partners were found to be a CF carrier. Nine couples had a risk of transmitting mutant CFTR allele to the offspring.Interpretation & conclusions:The heterogeneous spectrum of CFTR gene in Indian population suggests the necessity of screening CBAVD men and female partners for accurate genetic counselling prior to undergoing ICSI.

CFTR gene variants in Indian congenital bilateral absence of vas deferens & its relevance in genetic counselling.

CFTR gene variants in Indian congenital bilateral absence of vas deferens & its relevance in genetic counselling.

A novel mutation (−195C>A) in the promoter region of CFTR gene is associated with Chinese Congenital Bilateral Absence of Vas Deferens (CBAVD)

Congenital bilateral absence of vas deferens (CBAVD), a frequent cause of obstructive azoospermia and male infertility in Chinese, is mainly due to mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. This study aim to explore the promoter region of CFTR gene in CBAVD patients and study the mutations by functional analysis, and to discuss the significance of mutation testing in this area. We performed screening analysis on 65 CBAVD patients and 50 controls to detect mutations in the CFTR gene, and studied the functions of promoter mutations using reporter gene constructs, transient transfection techniques and subsequent assessment of transcriptional activity and expression levels. Mutations c.−195C>A and c.−34C>T in the promoter region of the CFTR gene were detected in 4 of our Chinese CBAVD patients, one of which was novel (c.−195C>A) and located in the conservative area, as well as the binding site of SP1 transcription factor through the prediction of bioinformatics analysis. By reverse transcription qPCR assay and luciferase assay, we validated it as a functional disease-causing variant that down-regulates the CFTR gene expression, and this effect was related to the amount of transcription factors. This study was the first to explore the promoter region of the CFTR gene in Chinese, and we believe that mutations in this region are associated with Chinese CBAVD patients. We also suggest a systematic strategy for genotyping Chinese CBAVD couples, which should help in developing reproductive counseling.