Loss of the AZFc region due to a human Y-chromosome microdeletion in infertile male patients

Abstract

ABSTRACT. Infertility is a major reproductive health threat; the frequency of male infertility due to Y-chromosome microdeletions is 13-18% in the human population; these microdeletions involve recurrent loss of three non-overlapping regions designated as AZFa, AZFb and AZFc, associated with spermatogenic failure. Several contradictory reports have been published regarding deletion frequency based on sequence-tagged site markers and genotypephenotype correlation. We examined the prevalence of Yq-deletion in 64 clinically diagnosed infertile male patients. We found a 3% frequency of microdeletion of the AZFc region; hormone profiles (FSH, LH and testosterone) showed significantly (P < 0.001) elevated levels compared to controls. No mutations were observed in the AZFa and AZFb regions, perhaps due to the selective use of sequencetagged site markers.

Investigation of AZF microdeletions in patients with Klinefelter syndrome

“…AZF can be further subdivided into 3 regions, including AZFa, AZFb, and AZFc. Each region contains several candidate genes involved in different stages of spermiogenesis, and deletions or mutations in these genes may cause spermatogenesis disorder, resulting in oligozoospermia or azoospermia (Pandey et al, 2010). In addition, some scholars identified a region known as AZFd between AZFb and AZFc (Kent-First et al, 1999).…”

Y-chromosome microdeletion and male infertility: a systematic review

“…Its etiopathogenesis is not well understood, however, it's known the importance of the role of microdeletion of subregions of the Ychromosome in the casuistry. The literature indicates that deletion of AZF, especially AZFc [12,19,32], is related to azoospermia [1,5,10,18,21,26,31,35], oligozoospermia [10,18,21,31,36] , infertility [4,24] or even normal fertility [7]. The absence of other loci is also underlined by the evidence: AZFa, AZFb, AZFd [10,20,21,23,25,29] and although the prevalence rates are not equidistant.…”

“…However, Pandey et al [24] show that hormonal levels (FSH, LH and testosterone) showed significantly higher (P <0.001) in relation to controls, when evaluated 64 men with infertility, of which 3% were in AZFc microdeletion. São Pedro et.…”

“…al. [24] there was the frequency of 3% of the AZFc microdeletion region, and no mutations were observed in AZFa and AZFb regions, maybe due to selective use of sequences of markers.…”

“…Surveys also show changes in the male hormone physiology varying the levels of testosterone/LH/FSH [17,25] as well as modifying the gonadal morphology in individuals affected by the microdeletion of Y-chromosome [24,35].…”