Possible germ cell-Sertoli cell interactions are critical for establishing appropriate expression levels for the Sertoli cell-specific MicroRNA, miR-202-5p, in human testis.

BACKGROUND: To examine human microRNA expression in fertile men and subsequently to compare expression patterns of miRNAs in fertile and infertile men, specifically men with Sertoli Cell Only (SCO) histopathology. METHODS: Testicular tissues from men with azoospermia and SCO, as well as those of men with normal spermatogenesis, were analyzed. MicroRNA was isolated using the miRCURY™ RNA Purification Kit. A miRCURY LNA™ Universal RT system was used for detection of microRNA by quantitative real-time PCR. MicroRNA localization was performed by in situ hybridizations (ISH) on formalin-fixed paraffin embedded (FFPE) tissue utilizing miRCURY LNA™ microRNA ISH technology. Statistical analysis was performed by GenEx V5.0. RESULTS: MicroRNA expression was determined for 13 normal fertile men and 5 men with the confirmed diagnosis of diffuse SCO. MiR-202-5p expression was reduced by 17-fold (P < 0.00001) in tissue from SCO men compared to normal. MiR-34c-5p was reduced by 346-fold (P < 0.00001), miR-10b was reduced 18-fold (P < 0.00001), miR-191 was reduced 20-fold (P = 0.001) and miR-126 was reduced 40-fold (P < 0.00001)) in tissues from SCO compared to normal fertile men. Using ISH, miR-202-5p was localized to Sertoli cells of men with normal spermatogenesis, but not in the Sertoli cells of men with SCO. CONCLUSION: Number of miRNAs are differentially expressed in normal fertile men compared to men with SCO. MicroRNA-202-5p is localized to Sertoli cells and its expression dramatically differs between fertile men and men whose germ cells are depleted, suggesting a novel interaction for regulating microRNA expression between the somatic and germ cell components of the seminiferous epithelium.

OBJECTIFS: Evaluer l'expression des microARN chez des hommes féconds puis comparer les profils d'expression de ces miRNAs chez des hommes féconds et des inféconds qui présentent plus particulièrement un syndrome de Sertoli seules (SCO) à l'histologie testiculaire. MATÉRIEL ET MÉTHODES: Ont été analysés des tissues testiculaires d'hommes avec azoospermie et SCO ainsi que ceux d'hommes avec spermatogenèse normale. Les miRNAs ont été isolés avec la trousse de Purification miRCURY™ RNA. Le système miRCURY LNA™ Universal RT a été utilisé pour la détection quantitative de miARNs par PCR en temps réel. La localisation des miARNs a été réalisée par hybridation in situ (HIS) sur des tissus fixés au formol et inclus en paraffine en utilisant la technologie miRCURY LNA™ microRNA ISH. Les analyses statistiques ont été faites avec GenEx V5.0. RÉSULTATS: L'expression des microARNs a été faite chez 13 hommes féconds et 5 hommes avec un diagnostic confirmé de SCO diffus. L'expression de miR-202-5p est réduite d'un facteur 17 (P < 0.00001) dans le tissu des hommes SCO par rapport au tissu des hommes à spermatogenèse normale. L'expression de miR-34c-5p est réduite d'un facteur 346 (P < 0.00001), celle de miR-10b d'un facteur 18 (P < 0.00001), celle de miR-191 d'un facteur 20 (P = 0.001) et celle de miR-126 d'un facteur 40 (P < 0.00001) dans les tissus des hommes SCO comparés à ceux des hommes à spermatogenèse normale. MiR-202-5p a été localisé par HIS dans les cellules de Sertoli des hommes à spermatogenèse normale, mais pas dans les cellules de Sertoli des hommes SCO. CONCLUSIONS: Nombre de miARNs sont exprimés différentiellement chez les hommes féconds par rapport aux hommes SCO. MicroARN-202-5p est localisé dans les cellules de Sertoli et son expression diffère de façon marquée entre les hommes féconds et ceux dont les cellules germinales sont absentes; ceci suggère une nouvelle interaction ­ entre les cellules somatiques et germinales constitutives de l'épithélium séminifère ­ impliquée dans la régulation de l'expression des microARNs.

Ubiquitin Specific Protease 26 (USP26) expression analysis in human testicular and extragonadal tissues indicates diverse action of USP26 in cell differentiation and tumorigenesis.

Ubiquitin specific protease 26 (USP26), a deubiquitinating enzyme, is highly expressed early during murine spermatogenesis, in round spermatids, and at the blood-testis barrier. USP26 has also been recognized as a regulator of androgen receptor (AR) hormone-induced action involved in spermatogenesis and steroid production in in vitro studies. Prior mutation screening of USP26 demonstrated an association with human male infertility and low testosterone production, but protein localization and expression in the human testis has not been characterized previously. USP26 expression analysis of mRNA and protein was completed using murine and human testis tissue and human tissue arrays. USP26 and AR mRNA levels in human testis were quantitated using multiplex qRT-PCR. Immunofluorescence colocalization studies were performed with formalin-fixed/paraffin-embedded and frozen tissues using primary and secondary antibodies to detect USP26 and AR protein expression. Human microarray dot blots were used to identify protein expression in extra-gonadal tissues. For the first time, expression of USP26 and colocalization of USP26 with androgen receptor in human testis has been confirmed predominantly in Leydig cell nuclei, with less in Leydig cell cytoplasm, spermatogonia, primary spermatocytes, round spermatids, and Sertoli cells. USP26 likely affects regulatory proteins of early spermatogenesis, including androgen receptor with additional activity in round spermatids. This X-linked gene is not testis-specific, with USP26 mRNA and protein expression identified in multiple other human organ tissues (benign and malignant) including androgen-dependent tissues such as breast (myoepithelial cells and secretory luminal cells) and thyroid tissue (follicular cells). USP26/AR expression and interaction in spermatogenesis and androgen-dependent cancer warrants additional study and may prove useful in diagnosis and management of male infertility.

Novel methylation specific real-time PCR test for the diagnosis of Klinefelter syndrome.

The aim of this study was to design a molecular assay for the diagnosis of Klinefelter syndrome (KS), based on the detection of supernumerary X-chromosomes (X-chs). DNA was extracted from peripheral blood samples of twenty-six 47,XXY males; two 46,XY/47,XXY males; twenty-two 46,XY males; and 15 females; and deaminated. Methylation-specific quantitative polymerase chain reaction (MS-qPCR) was performed using primers for unmethylated and methylated copies of the X-ch inactive-specific transcript (XIST-U and XIST-M) gene. X-ch disomy was determined on the basis of XIST methylation status. Degree of mosaicism in the 46,XY/47,XXY males was compared with karyotype and fluorescent in situ hybridization (FISH) results. Data analysis was performed using the Roche® LightCycler software V. 3.5.3., including determination of crossing points (CPs) by fit-point analysis and melting curve analysis. X-ch disomy was detected in all female controls and KS patients; male controls expressed XIST-M only. CPs ranged from 29.5 to 32.5 (standard deviation (s.d.) 0.8) for XIST-U and from 29 to 31 (s.d. 0.6) for XIST-M. Limit of detection of mosaicism was 1%. Based on XIST-U/XIST-M ratios for the two 47,XXY/46,XY patients, the calculated degree of mosaicism (1.8% and 17.8%) was comparable to FISH results (2.3% and 15%, respectively). Turnaround time from DNA deamination to final data analysis was under 9 h. We conclude that MS-qPCR is a sensitive, specific and rapid test for the detection of X-ch disomy, with applicability for the screening and diagnosis of KS, even in the setting of low grade 47,XXY/46,XY mosaicism.

Activation of GPER-1 estradiol receptor downregulates production of testosterone in isolated rat Leydig cells and adult human testis.

PURPOSE: Estradiol (E2) modulates testicular functions including steroidogenesis, but the mechanisms of E2 signaling in human testis are poorly understood. GPER-1 (GPR30), a G protein-coupled membrane receptor, mediates rapid genomic and non-genomic response to estrogens. The aim of this study was to evaluate GPER-1 expression in the testis, and its role in estradiol dependent regulation of steroidogenesis in isolated rat Leydig cells and human testis. MATERIALS AND METHODS: Isolated Leydig cells (LC) from adult rats and human testicular tissue were used in this study. Expression and localization studies of GPER-1 were performed with qRT-PCR, immunofluorescence, immunohistochemistry and Western Blot. Luteinizing Hormone (LH) -stimulated, isolated LC were incubated with estradiol, G-1 (GPER-1-selective agonist), and estrogen receptor antagonist ICI 182,780. Testosterone production was measured with radioimmunoassay. LC viability after incubation with G-1 was measured using 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, inner salt (MTS) assay. RESULTS: GPER-1 mRNA is abundantly expressed in rat LC and human testis. Co-localization experiments showed high expression levels of GPER-1 protein in LC. E2-dependent activation of GPER-1 lowers testosterone production in isolated rats LCs and in human testis, with statistically and clinically significant drops in testosterone production by 20-30% as compared to estradiol-naïve LC. The exposure to G-1 does not affect viability of isolated LCs. CONCLUSIONS: Our results indicate that activation of GPER-1 lowers testosterone levels in the rat and human testis. The expression of GPER-1 in human testis, which lack ERα, makes it an exciting target for developing new agents affecting testosterone production in men.

Bulbocavernosus muscle area measurement: a novel method to assess androgenic activity.

Serum testosterone does not correlate with androgen tissue activity, and it is critical to optimize tools to evaluate such activity in males. Ultrasound measurement of bulbocavernosus muscle (BCM) was used to assess the relationship between the number of CAG repeats (CAGn) in the androgen receptor (AR) and the BCM size; the changes in the number of CAGn over age were also evaluated. Transperineal ultrasound measurement of the BCM was also performed. AR CAGn were determined by high performance liquid chromatography, and morning hormone levels were determined using immunoassays. Forty-eight men had CAG repeat analysis. Twenty-five were <30 years of age, mean 23.7 years (s.d. = 3.24) and 23 were >45 years of age, mean 53 years (s.d. = 5.58). The median CAGn was 21 (13-29). BCM area was greater when the number of CAGn were <18 as compared to the number of CAGn >24 (P = 0.04). There was a linear correlation between the number of CAGn and the BCM area R 2 = 16% (P = 0.01). In the 45 to 65-years-old group, a much stronger negative correlation (R 2 = 29%, P = 0.01) was noticed. In the 19 to 29-years-old group, no such correlation was found (R 2 = 4%, P = 0.36). In older men, the number of CAGn increased with age (R 2 = 32%, P = 0.01). The number of CAGn in the AR correlates with the area of the BCM. Ultrasound assessment of the BCM is an effective surrogate to evaluate end-organ activity of androgens. The number of CAGn may increase with age.

Deletion or underexpression of the Y-chromosome genes CDY2 and HSFY is associated with maturation arrest in American men with nonobstructive azoospermia.

Maturation arrest (MA) refers to failure of germ cell development leading to clinical nonobstructive azoospermia. Although the azoospermic factor (AZF) region of the human Y chromosome is clearly implicated in some cases, thus far very little is known about which individual Y-chromosome genes are important for complete male germ cell development. We sought to identify single genes on the Y chromosome that may be implicated in the pathogenesis of nonobstructive azoospermia associated with MA in the American population. Genotype-phenotype analysis of 132 men with Y-chromosome microdeletions was performed. Protein-coding genes associated with MA were identified by visual analysis of a genotype-phenotype map. Genes associated with MA were selected as those genes within a segment of the Y chromosome that, when completely or partially deleted, were always associated with MA and absence of retrievable testicular sperm. Expression of each identified gene transcript was then measured with quantitative RT-PCR in testicular tissue from separate cohorts of patients with idiopathic MA and obstructive azoospermia. Ten candidate genes for association with MA were identified within an 8.4-Mb segment of the Y chromosome overlapping the AZFb region. CDY2 and HSFY were the only identified genes for which differences in expression were observed between the MA and obstructive azoospermia cohorts. Men with obstructive azoospermia had 12-fold higher relative expression of CDY2 transcript (1.33 ± 0.40 vs. 0.11 ± 0.04; P=0.0003) and 16-fold higher expression of HSFY transcript (0.78 ± 0.32 vs. 0.05 ± 0.02; P=0.0005) compared to men with MA. CDY2 and HSFY were also underexpressed in patients with Sertoli cell only syndrome. These data indicate that CDY2 and HSFY are located within a segment of the Y chromosome that is important for sperm maturation, and are underexpressed in testicular tissue derived from men with MA. These observations suggest that impairments in CDY2 or HSFY expression could be implicated in the pathogenesis of MA.

Methylation-specific PCR allows for fast diagnosis of X chromosome disomy and reveals skewed inactivation of the X chromosome in men with Klinefelter syndrome.

Klinefelter syndrome (KS) remains the most common, yet often undiagnosed, chromosomal aberration in men. Early diagnosis and treatment can improve the health of patients with KS. The aim of this study was to evaluate the inactivation pattern of supernumerary X chromosomes. The secondary aim was to design a reliable and cost-effective molecular test for detection of X chromosome disomy. Methylation-specific polymerase chain reaction (M-PCR), with primers for familial mental retardation (FMR1) and X chromosome inactive-specific transcript (XIST) genes, was used to detect the presence of X chromosome disomy in men. Seventeen fertile males, 12 females, and 35 males with KS (28 with 47,XXY karyotype, and 7 with 47,XXY/46,XY mosaics) were included in the study. Results of the karyotype were compared with the results of semiquantitative M-PCR. Inactivation of X chromosomes was measured by XIST/FMR-1 methylation ratio. Differences in the methylation patterns of FMR1 and XIST genes between 46,XY men and men with X chromosome disomy allowed for rapid detection of the presence of an additional X chromosome, achieving 100% sensitivity and specificity using M-PCR. The methylated:unmethylated FMR1 amplicon ratio allowed the detection of 1 additional X chromosome per 100 normal XY cells (1% of XX/XY mosaicism). In our series, 50% of 47,XXY men showed skewed inactivation of the X chromosome. Men with KS can have incomplete inactivation of supernumerary X chromosomes. M-PCR is a sensitive, specific, fast, and relatively inexpensive test for the diagnosis of X chromosome disomy.

Heat shock factor Y chromosome (HSFY) mRNA level predicts the presence of retrievable testicular sperm in men with nonobstructive azoospermia.

OBJECTIVE: To evaluate heat shock factor Y chromosome (HSFY) mRNA as a biomarker for the presence of retrievable testicular sperm. DESIGN: Case-control study. SETTING: Academic medical center. PATIENT(S): Men with nonobstructive azoospermia (NOA). INTERVENTION(S): Testicular tissue from men with successful or failed testicular sperm extraction was evaluated with qunatitative real-time polymerase chain reaction (qRT-PCR) for expression of HSFY mRNA. MAIN OUTCOME MEASURE(S): Area under the receiver operating characteristic curve (AUC), sensitivity, specificity, and probability of sperm retrieval based on HSFY testing. RESULT(S): We found higher HSFY mRNA expression in testicular tissue from NOA patients in whom sperm were successfully retrieved compared with those in whom sperm were not found, with good discrimination between the groups in all histologic variants of NOA (AUC 0.89 overall, 0.98 for patients with Sertoli cell only [SCO] histology, 0.90 for patients with maturation arrest [MA] histology). Sensitivity and specificity were, respectively, 67% and 93% overall, 92% and 100% for SCO patients, and 67% and 92% for MA patients. The probabilities of sperm retrieval for HSFY-positive and -negative patients were, respectively, 93% and 31% overall, 100% and 7% for SCO patients, and 91% and 32% for MA patients. CONCLUSION(S): Detection of HSFY mRNA expression by qRT-PCR has promising application in the evaluation and counseling of men with NOA before attempted sperm retrieval surgery.

Aberrations in pseudoautosomal regions (PARs) found in infertile men with Y-chromosome microdeletions.

CONTEXT: The pseudoautosomal regions (PARs) of the Y-chromosome undergo meiotic recombination with the X-chromosome. PAR mutations are associated with infertility and mental and stature disorders. OBJECTIVE: The aim of the study was to determine whether men with Y-chromosome microdeletions have structural defects in PARs. DESIGN AND PARTICIPANTS: Eighty-seven infertile men with Y-chromosome microdeletions and 35 controls were evaluated for chromosomal rearrangements using commercial or custom (X- and Y-chromosome) array comparative genomic hybridization or by quantitative PCR of selected PAR genes. Multisoftware-defined chromosomal gains or losses were validated by quantitative PCR and FISH. RESULTS: Array comparative genomic hybridization confirmed the AZF deletions identified by multiplex PCR. All men with Y-chromosome microdeletions and an abnormal karyotype displayed PAR abnormalities, as did 10% of men with Y-chromosome microdeletions and a normal karyotype. None of the control subjects or infertile men without Y-chromosome microdeletions had PAR duplications or deletions. SHOX aberrations occurred in 14 men (nine gains and five losses); four were short in stature (<10th percentile), and one was tall (>95th percentile). In contrast, the height of 23 men with Y-chromosome microdeletions and normal PARs was average at 176.8 cm (50th percentile). CONCLUSIONS: Y-chromosome microdeletions can include PAR defects causing genomic disorders such as SHOX, which may be transmitted to offspring. Previously unrecognized PAR gains and losses in men with Y-chromosome microdeletions may have consequences for offspring.

Diagnosis of the gr/gr Y chromosome microdeletion does not help in the treatment of infertile American men.

PURPOSE: The phenotypic effects of the gr/gr partial azoospermia factor c deletion vary geographically and to our knowledge have not been reported in the American population. We evaluated the clinical characteristics of infertile American men with the gr/gr deletion. MATERIALS AND METHODS: We retrospectively reviewed clinical data on 1,410 infertile men tested for the gr/gr deletion. We analyzed sperm concentration and the outcome of microdissection testicular sperm extraction with respect to gr/gr status. RESULTS: We identified 73 men with gr/gr deletions, including 43 of 989 (4.3%) with azoospermia, 18 of 317 (5.7%) with severe oligospermia (less than 5 million sperm per ml), 6 of 61 (9.8%) with oligospermia (5 to less than 20 million sperm per ml) and 6 of 43 (14%) infertile men with normospermia (greater than 20 million sperm per ml). A gr/gr deletion correlated with higher sperm production. The gr/gr deletion rate was higher in men with normospermia than in those with a sperm concentration of less than 20 million and less than 5 million per ml (p = 0.021 and 0.006, respectively). Microdissection testicular sperm extraction was done in 22 azoospermic men with gr/gr deletions and sperm were retrieved in 14 (64%). This retrieval rate was similar to that at our center in men with idiopathic nonobstructive azoospermia (p = 0.13). CONCLUSIONS: Diagnosis of the gr/gr deletion did not predict impaired sperm production in our patient population and did not appear to alter the prognosis for surgical sperm retrieval. Despite the established modulatory impact of the gr/gr deletion on sperm production in some populations at this time the clinical value of testing infertile American men for the gr/gr deletion is not clear.

A decade of experience emphasizes that testing for Y microdeletions is essential in American men with azoospermia and severe oligozoospermia.

OBJECTIVE: To evaluate the benefit of Y microdeletion testing. DESIGN: Retrospective analysis. SETTING: University-based male fertility clinic and genetics laboratory. PATIENT(S): A total of 1,591 men with sperm concentrations less than 5 million sperm/mL. INTERVENTION(S): Semen analysis, Y microdeletion testing, microdissection testicular sperm extraction (TESE). MAIN OUTCOME MEASURE(S): Sperm concentration, incidence and nature of Y microdeletions, microdissection TESE outcome. RESULT(S): We identified 149 microdeletions (9.4%). 10.4% of azoospermic men and 10.1% of men with sperm concentrations >0-1 million sperm/mL harbored microdeletions. Two-thirds of microdeletions in azoospermic men were AZFa, AZFb, AZFb+c, or complete Yq deletions. Virtually all microdeletions in oligozoospermic patients were AZFc deletions. Seven hundred eighteen patients underwent microdissection TESE, including 41 with microdeletions. Microdissection TESE failed in all patients with AZFa, AZFb, AZFb+c, and complete Yq deletions. Sperm were retrieved in 15/21 AZFc deleted patients (71.4%). The presence of an AZFc deletion was associated with increased likelihood of sperm retrieval when compared with the 48.8% retrieval rate in 385 idiopathically azoospermic men who consecutively underwent microdissection TESE at our institution during the study period. Clinical pregnancy was achieved in 10/15 azoospermic AZFc deleted patients for whom sperm were successfully retrieved. CONCLUSION(S): Of azoospermic and severely oligozoospermic American men, 10% harbor Y microdeletions that alter prognosis for surgical sperm retrieval and are vertically transmissible. Y microdeletion testing is essential for genetic and preoperative counseling in these patients.

Normal female phenotype and ovarian development despite the ovarian expression of the sex-determining region of Y chromosome (SRY) in a 46,XX/69,XXY diploid/triploid mosaic child conceived after in vitro fertilization-intracytoplasmic sperm injection.

CONTEXT: Diploid/triploid mosaicism (mixoploidy) is a rare chromosomal abnormality characterized by mental and growth retardation, hypotonia, and dysmorphic features such as facial asymmetry, low-set ears, and syndactyly. All 46,XX/69,XXY cases fall into three phenotypic groups: male with testicular development, ovotestis disorder of sex development (DSD), or undervirilized male DSD. All phenotypic females with diploid/triploid mosaic reported so far had 46,XX/69,XXX karyotype. PATIENT: We report an 8-year-old girl conceived after in vitro fertilization-intracytoplasmic sperm injection with normal internal/external genital and ovarian development despite 46,XX/69,XXY mosaicism and normal expression of sex-determining region of Y chromosome (SRY) in her gonads. INTERVENTION: Because of the increased risk of gonadoblastoma resulting from Y chromosome mosaicism, her ovaries were removed by laparoscopy. Ovarian tissue was analyzed histologically as well as by fluorescence in situ hybridization, PCR, and RT-PCR amplification to determine the localization of Y chromosome and expression of SRY and DAX1 mRNA. Methylation-specific PCR was used to assess the inactivation pattern of X chromosomes. RESULTS: By laparoscopy, internal female genital anatomy appeared to be normal. Cytogenetic and molecular methods confirmed the presence of intact and functionally active Y chromosome in the ovary. Strikingly, histological assessment of the gonads showed normal ovarian architecture with abundant primordial follicles despite the presence of the Y chromosome in ovarian follicles and the expression of SRY mRNA in gonadal tissue. CONCLUSION: This case illustrates that normal ovarian development is possible in the presence of Y chromosome in ovarian follicles and despite the expression of SRY in ovarian tissue. Furthermore, this is the first documented case of mixoploidy after in vitro fertilization-intracytoplasmic sperm injection and the only phenotypic female with 46,XX/69,XXY karyotype.

Identification of polymorphisms and balancing selection in the male infertility candidate gene, ornithine decarboxylase antizyme 3.

BACKGROUND: The antizyme family is a group of small proteins that play a role in cell growth and division by regulating the biosynthesis of polyamines (putrescine, spermidine, spermine). Antizymes regulate polyamine levels primarily through binding ornithine decarboxylase (ODC), an enzyme key to polyamine production, and targeting ODC for destruction by the 26S proteosome. Ornithine decarboxylase antizyme 3 (OAZ3) is a testis-specific antizyme paralog and the only antizyme expressed in the mid to late stages of spermatogenesis. METHODS: To see if mutations in the OAZ3 gene are responsible for some cases of male infertility, we sequenced and evaluated the genomic DNA of 192 infertile men, 48 men of known paternity, and 34 African aborigines from the Mbuti tribe in the Democratic Republic of the Congo. The coding sequence of OAZ3 was further screened for polymorphisms by SSCP analysis in the infertile group and an additional 250 general population controls. Identified polymorphisms in the OAZ3 gene were further subjected to a haplotype analysis using PHASE 2.02 and Arlequin 2.0 software programs. RESULTS: A total of 23 polymorphisms were identified in the promoter, exons or intronic regions of OAZ3. The majority of these fell within a region of less than two kilobases. Two of the polymorphisms, -239 A/G in the promoter and 4280 C/T, a missense polymorphism in exon 5, may show evidence of association with male infertility. Haplotype analysis identified 15 different haplotypes, which can be separated into two divergent clusters. CONCLUSION: Mutations in the OAZ3 gene are not a common cause of male infertility. However, the presence of the two divergent haplotypes at high frequencies in all three of our subsamples (infertile, control, African) suggests that they have been maintained in the genome by balancing selection, which was supported by a test of Tajima's D statistic. Evidence for natural selection in this region implies that these haplotypes may be associated with a trait other than infertility. This trait may be related to another function of OAZ3 or a region in tight linkage disequilibrium to the gene.

Screening the SPO11 and EIF5A2 genes in a population of infertile men.

Populations of infertile and fertile men were screened for mutations in SPO11 and EIF5A2, two infertility candidate genes. Three heterozygous amino acid changes that might contribute to infertility were identified in the infertile group.

Novel mutations in testis-specific ubiquitin protease 26 gene may cause male infertility and hypogonadism.

Patients (n = 188) with non-obstructive azoospermia (NOA), and 17 fertile controls were screened for sequence changes in the ubiquitin specific protease (USP) 26 gene. Semen analysis, hormonal evaluation, and testicular biopsies were performed. DNA was extracted from whole blood. Denaturing high-performance liquid chromatography was used to screen for single nucleotide polymorphisms. Amino acid sequences were determined in samples with mutations. Twenty out of 188 (10.6%) infertile men had amino acid changes in USP26. No changes were found in fertile controls. 1090C-->T substitution and (363insACA; 494T-->C; 1423C-->T) change were found in 3.3 and 1.9% of patients respectively. Serum testosterone concentrations and testicular volume were lower in the mutation positive group compared with the non-mutation group (272 versus 366 ng/dl; P = 0.01) (volume: 7.88 versus 10 ml, P = 0.03). Six out of 28 (21%) patients with Sertoli cell-only syndrome, and two out of 18 (11%) patients with maturation arrest had mutations in the USP26 gene. There were no live deliveries in couples with the USP26+ mutation, and three live deliveries in the group without mutations. The USP26 gene may be of importance in male reproduction. Mutations in this gene may be associated with male infertility, and may negatively affect testicular function.

AZF microdeletions of the Y chromosome and in vitro fertilization outcome.

OBJECTIVE: To determine whether the presence of a Y microdeletion confers any adverse effects on in vitro fertilization or intracytoplasmic sperm injection (IVF/ICSI) outcome. DESIGN: Retrospective case-control study. SETTING: Academic infertility center. PATIENT(S): A total of 17 patients with Y microdeletions who attempted IVF/ICSI cycles at our center between March 1996 and March 2002 were studied. Study patients were analyzed in two groups: those who underwent testicular sperm extraction (TESE) and those for whom ejaculated sperm was used. INTERVENTION(S): The two patient study groups were matched to controls treated at the same time who had either nonobstructive severe oligozoospermia or azoospermia with normal Y chromosomes. Controls were matched for age of the female partner, sperm concentration, and number of embryos transferred. MAIN OUTCOME MEASURE(S): Fertilization and clinical pregnancy rates. RESULT(S): Sperm was only obtained from patients with azoospermic factor (AZF)c microdeletions (and from one patient with a partial AZFb microdeletion). A trend toward lower fertilization rates in patients with Y microdeletions was noted, which did not reach statistical significance. Clinical pregnancy rates per cycle and per transfer were similar to those for controls. CONCLUSION(S): Patients with AZFc microdeletions seem to have IVF/ICSI outcomes comparable to those of controls with normal Y chromosomes.