Screening for AZF Deletion in a Large Series of Severely Impaired Spermatogenesis Patients

TLDR: Because men with severe infertility suffer a high risk of Y chromosome deletion, screening for these men is recommended prior to treatment with assisted reproduction.

Abstract: Recent investigations have pointed to a high prevalence of Y chromosome submicroscopic deletions in men with severely im- paired spermatogenesis. We report on the incidence in 128 infertile men, in whom karyotype, sperm count, and hormonal parameters were evaluated. Patients with abnormal karyotype (other than an ab- normal Y chromosome) or sperm concentration of more than 2 million/ mL were excluded. Genomic DNA was extracted from the peripheral leukocytes of 57 men with azoospermia and 71 with severe oligo- spermia. Molecular analysis was performed by 3 multiplex polymerase chain reactions using a set of 9 sequence tagged sites (STSs) from 3 different regions of the Y chromosome: AZFa, AZFb, and AZFc. In 7% of the studied patients Yq microdeletions were detected, with a high prevalence in men with azoospermia (14%). No deletions were detected in the AZFa region. Deletions were present in AZFb, AZFc, or both regions. The deletion observed in 1 patient that did not overlap with the DAZ region demonstrates that genes other than DAZ may also be involved in the pathogenesis of some subsets of male infer- tility. Furthermore, common Yq deletions present different testicular pictures, suggesting that some unknown factors may be disturbing spermatogenesis. Because men with severe infertility suffer a high risk of Y chromosome deletion, screening for these men is recommended prior to treatment with assisted reproduction.