Y Yang1, M Ma, L Li, W Zhang, C Xiao, S Li, Y Ma, D Tao, Y Liu, L Lin, S Zhang. 1. Department of Medical Genetics and State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Chengdu, P R China.
Abstract
INTRODUCTION: Y chromosomes are genetically highly variable due to frequent structural rearrangements. The variations may create a genetic background for the susceptibility to Y-related spermatogenic impairment, although few data have been accumulated about the possible correlation between the Y-chromosome haplotype and the predisposition of men to spermatogenic failure. OBJECTIVE: To investigate the possible association of Y-chromosome background with spermatogenic failure. METHODS: The distribution of 18 Y-chromosome haplogroups was compared between 414 infertile men with azoospermia or oligozoospermia and 262 normozoospermic men with or without AZFc deletions in a Han population of Southwest China. RESULTS: A significant population difference in Y-haplogroup distribution was found between the groups of normozoospermia and azoospemia or oligozoospermia, and between the patient groups with oligozoospermia and azoospermia without AZFc deletions. Interpopulation comparison of Y haplogroup frequencies showed that the distribution of the haplogroups C, K* and O3* were significantly different between the groups. CONCLUSION: This study provides evidence for the association of Y-chromosome background with impaired spermatogenesis, suggesting that Y variations play a role in the occurrence and even the severity of spermatogenic failure. Furthermore, both AZFc deletions and other Y-chromosome structural variations may be important for determining the susceptibility to spermatogenic failure. Our findings emphasise the necessity of more extensive study on Y-chromosome variations for better understanding of spermatogenesis and its pathology.
INTRODUCTION: Y chromosomes are genetically highly variable due to frequent structural rearrangements. The variations may create a genetic background for the susceptibility to Y-related spermatogenic impairment, although few data have been accumulated about the possible correlation between the Y-chromosome haplotype and the predisposition of men to spermatogenic failure. OBJECTIVE: To investigate the possible association of Y-chromosome background with spermatogenic failure. METHODS: The distribution of 18 Y-chromosome haplogroups was compared between 414 infertile men with azoospermia or oligozoospermia and 262 normozoospermic men with or without AZFc deletions in a Han population of Southwest China. RESULTS: A significant population difference in Y-haplogroup distribution was found between the groups of normozoospermia and azoospemia or oligozoospermia, and between the patient groups with oligozoospermia and azoospermia without AZFc deletions. Interpopulation comparison of Y haplogroup frequencies showed that the distribution of the haplogroups C, K* and O3* were significantly different between the groups. CONCLUSION: This study provides evidence for the association of Y-chromosome background with impaired spermatogenesis, suggesting that Y variations play a role in the occurrence and even the severity of spermatogenic failure. Furthermore, both AZFc deletions and other Y-chromosome structural variations may be important for determining the susceptibility to spermatogenic failure. Our findings emphasise the necessity of more extensive study on Y-chromosome variations for better understanding of spermatogenesis and its pathology.