Prevalence of Y chromosome deletions in a Brazilian population of nonobstructive azoospermic and severely oligozoospermic men

Abstract

We determined the prevalence of Y chromosome deletions in a population of 60 Brazilian nonobstructive azoospermic and severely oligozoospermic men. PCR-based screening of microdeletions was performed on lymphocyte DNA for the presence of 14 sequencetagged sites (STS) located in the azoospermic factor (AZF) on the Yq chromosome. All STS were amplified efficiently in samples from 12 fertile men tested, but failed to be amplified in samples from fertile women, indicating the specificity of PCR conditions for Yq screening. Overall, 4 of the 60 infertile patients tested (6.7%) exhibited deletion of the Y chromosome, 2 of them being severely oligozoospermic patients (P10 and P32) and 2 azoospermic men (patients P47 and P57). Patients P47 and P57 presented larger deletions in the AZFa, AZFb and AZFc subregions, with apparent loss of Yq material evidenced by karyotype analysis. Patients P10 and P32 presented deletions confined to the AZFc region, involving the DAZ locus. Male relatives of patients P10 and P32 had no Y chromosome deletions and presented a normal karyotype, suggesting a de novo status of the deletions found. Our data add to the growing literature showing that microdeletions of the Y chromosome can be the cause of male idiopathic infertility.

Male infertility in China: laboratory finding for AZF microdeletions and chromosomal abnormalities in infertile men from Northeastern China

“…This is consistent with the frequencies reported by other centers, which range from 3% to 55% [1,16,17]. The prevalence of AZF microdeletion in the patients with azoospermia, oligozoospermia and oligo-asteno-teratozoospermia syndrome was 9.1%, 9.5% and 8.3%, respectively.…”

Cytogenetic and Y chromosome microdeletion screening studies in infertile males with Oligozoospermia and Azoospermia in Southeast Turkey

“…Analysis of these deletions demonstrates in the AZF region four nonoverlaping loci, AZFa, AZFb, AZFc and AZFd, localized between AZFb and AZFc [2,3,6,[8][9][10][11][15][16][17]. Deletion of these loci results in spermatogenic arrest and is associated with azoospermia and oligozoospermia [2,3,6,[8][9][10][11][15][16][17].…”

“…Deletion of these loci results in spermatogenic arrest and is associated with azoospermia and oligozoospermia [2,3,6,[8][9][10][11][15][16][17]. These AZF genes code for RNA binding proteins and may be involved in regulation of gene expression, RNA metabolism, packaging and transport to cytoplasm, and RNA splicing [7,10,15,17].…”

“…However, this procedure might have a potential risk of transmitting genetic abnormalities to the offspring, since the natural selection process of sperm cells is bypassed [5-8, 11, 13, 17]. In view of the genetic risks for the next generation, the importance of careful evaluation of karyotypes and AZF microdeletions in male infertility prior to assisted reproduction by ICSI is evident [5,6,17]. Therefore, in the present study, it is aimed to investigate the frequency and types of both major chromosomal abnormalities by using standard cytogenetic methods and Y chromosome microdeletions by using genebased multiplex polymerase chain reaction (PCR) of infertile men with azoospermia and oligozoospermia to give appropriate genetic counseling before assisted reproduction techniques in southeastern Turkey.…”

Male infertility in Northeast China: molecular detection of Y chromosome microdeletions in azoospermic patients with Klinefelter's syndrome

“…A series of 9 specific sequence-tagged sites (STSs) were selected for molecular genetic determination of microdeletions as follows: AZFa: SY84 and SY86; AZFb: SY127, SY134, and SY143; AZFc: SY157, SY254, and SY255; AZFd: SY152 (Wang et al, 2010). Human zinc-finger protein-encoding genes (ZFX/ZFY) located on the X and Y chromosomes were selected as internal control primers (SaoPedro et al, 2003;Arruda et al, 2007;Wang et al, 2010).…”