Male ; Humans ; Azoospermia/genetics* ; Infertility, Male/genetics* ; Mutation ; Homozygote

OBJECTIVETo analyze the pattern and prevalence of partial copy deletion of deleted-in-azoospermia (DAZ) gene in the azoospermia factor C(AZFc) region of patients with idiopathic azoospermia or severe oligozoospermia.

METHODSsY581 and sY587 in DAZ gene region were analyzed by polymerase chain reaction-restriction length polymorphism(PCR-RFLP) for its deletion in 197 patients with azoospermia, 166 patients with severe oligozoospermia, and 210 fertile men as controls.

RESULTSDeletion of both DAZ1 and DAZ2 was detected in 18 patients with azoospermia and 10 with severe oligozoospermia, and the prevalence was 9.1% and 6.0% respectively. There was significant difference in deletion rate between the cases and controls.

CONCLUSIONThe frequency of partial copy deletion of DAZ gene in Chinese idiopathic azoospermia or severe oligozoospermia patients is much higher than that of fertile controls, suggesting that the deletion of DAZ1/DAZ2 may be one of the important genetic etiological factors of spermatogenesis damage. The pattern and prevalence of DAZ partial copy deletion are similar to those of Caucasians populations, and detection of DAZ gene partial copy deletion by PCR-RFLP may be adopted as an additional clinical gene diagnostic measure after AZF microdeletion detection.

Azoospermia ; complications ; genetics ; Chromosomes, Human, Y ; genetics ; Deleted in Azoospermia 1 Protein ; Gene Deletion ; Humans ; Infertility, Male ; etiology ; genetics ; Male ; Models, Genetic ; Polymerase Chain Reaction ; RNA-Binding Proteins ; genetics

The Y chromosome contains genes closely related to male gonadal development and spermatogenesis. The azoospermia factor (AZF) is a gene on the long arm of the Y chromosome that regulates spermatogenesis, and its deletion can induce spermatogenic arrest and consequently male infertility. Most researchers subdivide AZF into AZFa, AZFb and AZFc, and some believe there to be another region, AZFd, between AZFa and AZFb. Different AZF deletions lead to different phenotypes. AZFc deletion, as the commonest type that attracts widespread attention of researchers, includes complete AZF deletion and partial AZF deletion, and the latter mainly consists of gr/gr deletion and b2/b3 deletion. The gr/gr deletion can cause infertility in some areas or in human species. The influence of b2/b3 deletion on spermatogenesis has not been confirmed, but its wide spread in haplogroup N has distribution scientists' attention. This review outlines the structures, candidate genes and deletions of AZF, especially AZFc, along with their relationship with spermatogenesis, so as to provide a theoretical basis for clinical prenatal diagnosis and treatment of infertility.
Azoospermia ; etiology ; genetics ; Chromosomes, Human, Y ; Gene Deletion ; Humans ; Infertility, Male ; etiology ; genetics ; Male ; Spermatogenesis ; genetics

Failure of spermatogenesis is the main clinical manifestation of male infertility. Multiple factors including genetic factors may affect spermatogenesis. Azoopermia factor (AZF) is closely involved in spermatogenesis. This paper reviews recent progress made in the study of AZF and its role in spermatogenesis and male infertility.
Azoospermia ; etiology ; genetics ; Humans ; Infertility, Male ; etiology ; genetics ; Male ; Spermatogenesis ; genetics

Apparently balanced chromosomal structural rearrangements are known to cause male infertility and account for approximately 1% of azoospermia or severe oligospermia. However, the underlying mechanisms of pathogenesis and etiologies are still largely unknown. Herein, we investigated apparently balanced interchromosomal structural rearrangements in six cases with azoospermia/severe oligospermia to comprehensively identify and delineate cryptic structural rearrangements and the related copy number variants. In addition, high read-depth genome sequencing (GS) (30-fold) was performed to investigate point mutations causative of male infertility. Mate-pair GS (4-fold) revealed additional structural rearrangements and/or copy number changes in 5 of 6 cases and detected a total of 48 rearrangements. Overall, the breakpoints caused truncations of 30 RefSeq genes, five of which were associated with spermatogenesis. Furthermore, the breakpoints disrupted 43 topological-associated domains. Direct disruptions or potential dysregulations of genes, which play potential roles in male germ cell development, apoptosis, and spermatogenesis, were found in all cases (n = 6). In addition, high read-depth GS detected dual molecular findings in case MI6, involving a complex rearrangement and two point mutations in the gene DNAH1. Overall, our study provided the molecular characteristics of apparently balanced interchromosomal structural rearrangements in patients with male infertility. We demonstrated the complexity of chromosomal structural rearrangements, potential gene disruptions/dysregulation and single-gene mutations could be the contributing mechanisms underlie male infertility.
Azoospermia/genetics* ; Chromosome Aberrations ; Humans ; Infertility, Male/genetics* ; Male ; Oligospermia/genetics* ; Translocation, Genetic

OBJECTIVE: To explore the characteristics of copy number variation (CNV) within the Y chromosome azoospermia factor (AZF) region in patients with spermatogenesis disorders in the Shenzhen area. METHODS: A total of 123 patients with spermatogenesis disorders who had visited Shenzhen People's Hospital from January 2016 to October 2022 (including 73 patients with azoospermia and 50 patients with oligozoospermia) and 100 normal semen males were selected as the study subjects. The AZF region was detected with multiplex ligation-dependent probe amplification (MLPA), and the correlation between the CNV in the AZF region and spermatogenesis disorders was analyzed using the chi-square test or Fisher's exact test. RESULTS: 19 CNV were detected among 53 patients from the 223 samples, including 20 cases (27.40%, 20/73) from the azoospermia group, 19 cases (38%, 19/50) from the oligozoospermia group, and 14 cases (14%, 14/100) from the normal control group. In the azoospermia, oligozoospermia, and normal control groups, the detection rates for CNV related to the AZFa region (including AZFab and AZFabc) were 5.48% (4/73), 2.00% (1/50), and 0 (0/100), respectively. The detection rates for the AZFb region (including the AZFbc region) were 6.85% (5/73), 0 (0/50), and 0 (0/100), respectively. The detection rates for gr/gr deletions in the AZFc region were 2.74% (2/73), 6.00% (3/50), and 9.00% (9/100), respectively, and those for b2/b4 deletions in the AZFc region were 2.74% (2/73), 10.00% (5/50), and 0 (0/100), respectively. The detection rates for complex rearrangements in the AZFc region were 6.85% (5/73), 18.00% (9/50), and 3.00% (3/100), respectively. Statistical analysis showed no significant difference in the detection rate of gr/gr deletions between the three groups (Fisher's Exact Test value = 2.712, P = 0.249); the differences in the detection rate of b2/b4 deletions between the three groups were statistically significant (Fisher's Exact Test value = 9.489, P = 0.002); the differences in the detection rate of complex rearrangements in the AZFc region between the three groups were statistically significant (Fisher's Exact Test value = 9.493, P = 0.006). In this study, a rare AZFa region ARSLP1 gene deletion (involving SY86 deletion) was detected in a patient with oligozoospermia. CONCLUSION CNV in the AZFa and AZFb regions have a severe impact on spermatogenesis, but partial deletion in the AZFa region (ARSLP1 gene deletion) has a minor impact on spermatogenesis. The b2/b4 deletion and complex rearrangement in the AZFc region may be risk factors for male infertility. The gr/gr deletion may not serve as a risk factor for male infertility in the Shenzhen area.
Humans ; Male ; Azoospermia/genetics* ; DNA Copy Number Variations ; Oligospermia/genetics* ; Infertility, Male/genetics* ; Y Chromosome

Nonobstructive azoospermia (NOA) is a common cause of infertility and is defined as the complete absence of sperm in ejaculation due to defective spermatogenesis. The aim of this study was to identify the genetic etiology of NOA in an infertile male from a Chinese consanguineous family. A homozygous missense variant of the membrane-bound O-acyltransferase domain-containing 1 (MBOAT1) gene (c.770C>T, p.Thr257Met) was found by whole-exome sequencing (WES). Bioinformatic analysis also showed that this variant was a pathogenic variant and that the amino acid residue in MBOAT1 was highly conserved in mammals. Quantitative polymerase chain reaction (Q-PCR) analysis showed that the mRNA level of MBOAT1 in the patient was 22.0% lower than that in his father. Furthermore, we screened variants of MBOAT1 in a broader population and found an additional homozygous variant of the MBOAT1 gene in 123 infertile men. Our data identified homozygous variants of the MBOAT1 gene associated with male infertility. This study will provide new insights for researchers to understand the molecular mechanisms of male infertility and will help clinicians make accurate diagnoses.
Acetyltransferases/genetics* ; Animals ; Azoospermia/genetics* ; Cell Cycle Proteins/genetics* ; Humans ; Infertility, Male/genetics* ; Male ; Mammals ; Membrane Proteins/genetics* ; Mutation

Thanks to tremendous advances in sequencing technologies and in particular to whole exome sequencing (WES), many genes have now been linked to severe sperm defects. A precise genetic diagnosis is obtained for a minority of patients and only for the most severe defects like azoospermia or macrozoospermia which is very often due to defects in the aurora kinase C (AURKC gene. Here, we studied a subject with a severe oligozoospermia and a phenotypic diagnosis of macrozoospermia. AURKC analysis did not reveal any deleterious variant. WES was then initiated which permitted to identify a homozygous loss of function variant in the zinc finger MYND-type containing 15 (ZMYND15 gene. ZMYND15 has been described to serve as a switch for haploid gene expression, and mice devoid of ZMYND15 were shown to be sterile due to nonobstructive azoospermia (NOA). In man, ZMYND15 has been associated with NOA and severe oligozoospermia. We confirm here that the presence of a bi-allelic ZMYND15 variant induces a severe oligozoospermia. In addition, we show that severe oligozoospermia can be associated macrozoospermia, and that a phenotypic misdiagnosis is possible, potentially delaying the genetic diagnosis. In conclusion, genetic defects in ZMYND15 can induce complete NOA or severe oligozoospermia associated with a very severe teratozoospermia. In our experience, severe oligozoospermia is often associated with severe teratozoospermia and can sometimes be misinterpreted as macrozoospermia or globozoospermia. In these instances, specific AURKC or dpy-19 like 2 (DPY19L2) diagnosis is usually negative and we recommend the direct use of a pan-genomic techniques such as WES.
Animals ; Azoospermia/genetics* ; Humans ; Infertility, Male/genetics* ; Male ; Membrane Proteins/genetics* ; Mice ; Mutation ; Oligospermia/genetics* ; Repressor Proteins/metabolism* ; Teratozoospermia/genetics*

OBJECTIVETo investigate the location and characteristics of microdeletions of Y chromosome azoospermia factor (AZF) genes in infertile males with azoospermia and severe oligozoospermia in southern Sichuan.

METHODSMultiplex PCR was used to detect 18 sequence tagged sites (STS) involved in Y chromosome AZF microdeletions among 224 infertile males (including 134 azoospermia cases and 90 severe oligozoospermia cases) and 70 healthy males.

RESULTSAmong the 224 infertile males, the overall frequency of microdeletions was 12.1% (27/224), and were 13.4% (18/134) in those with azoospermia and 10.0% (9/90) in those with severe oligozoospermia. The most frequent microdeletions have occurred in the AZFc region (51.9%). Compared with the 6 STS loci recommended by European Academy of Andrology and European Molecular Genetics Quality Network, 22.7% more deletions were detected based on the 18 STS loci selected from the AZF region.

CONCLUSIONIdentification of Y chromosome microdeletions has a significant implication on the diagnosis of male infertility. The most frequent microdeletions have occurred in the AZFc region in southern Sichuan. To use more sequence tagged sites for the screening can improve the reliability and detection rate of Y chromosome microdeletions.

Adult ; Azoospermia ; genetics ; Chromosome Deletion ; Chromosomes, Human, Y ; Female ; Humans ; Infertility, Male ; genetics ; Male ; Middle Aged

OBJECTIVETo locate the deletion region of an azoospermic patient with a large deletion on his Y chromosome long arm.

METHODSMultiplex polymerase chain reaction was used to amplify fifteen sequence tagged sites (STS), namely sY84, sY86, sY87 in AZFa, sY102, sY117, sY118, sY119, sY115, DYS132, DYS383, sY1015, sY121, sY125, sY127, sY129 and sY134 in AZFb, sY152 in AZFd, sY1258, sY1291, sY254, sY255, sY158 and sY1201 in AZFc, and sY160 in Yq12.

RESULTSOnly sY84, sY86, sY87, sY102, sY117, sY118, sY119, sY115 and DYS132 could be amplified while the others were negative. The breakpoints were found to locate in an area between AZFb sY115 and DYS383 spanning 8577.

CONCLUSIONThis study provided the exact breakpoints on Y chromosome AZF region in the patient.

Adult ; Azoospermia ; genetics ; Chromosome Deletion ; Chromosomes, Human, Y ; genetics ; Humans ; Male