Zhou-Cun A, Yang Yuan, Zhang Si-Zhong, Zhang Wei, Lin Li
Department of Medical Genetics, West China Hospital, Sichuan University, Division of Human Morbid Genomics, State Key Laboratory of Biotherapy, Chengdu 610041, China.
Yi Chuan Xue Bao. 2006 Feb;33(2):111-6. doi: 10.1016/s0379-4172(06)60029-2.
Chromosomal abnormality and Y chromosome microdeletion are regarded as two frequent genetic causes associated with spermatogenic failure in Caucasian population. To investigate the distribution of the two genetic defects in Chinese patients with azoospermia or severe oligozoospermia, karyotype analysis by G-banding was carried out in 358 idiopathic infertile men, including 256 patients with azoospermia and 102 patients with severe oligozoospermia, and screening of AZF region microdeletion of Y chromosome by multiplex PCR was performed in those patients without detectable chromosomal abnormality and 100 fertile controls. Of 358 patients, 39(10.9%) were found to have chromosomal abnormalities in which Klinefelter's syndrome (47, XXY) was the most common chromosomal aberration. The incidence of sex chromosomal abnormality in patients with azoospermia was significantly higher than that in patients with severe oligozoospermia (12.1% vs 1%). Among the rest of the 319 patients with normal karyotype, 46 (14.4%) were found to have microdeletions in AZF region. The prevalence rates of AZF microdeletion was 15% and 13.1% in patients with azoospermia and severe oligozoospermia respectively. The microdeletion in AZFc was the most frequent deletion and all the microdeletions in AZFa were found in azoospermic patients. No microdeletion in AZF region was detected in fertile controls. In conclusion, chromosomal abnormality and AZF region microdeletion of Y chromosome might account for about 25% of Chinese infertile patients with azoospermia or severe oligozoospermia, suggesting the two abnormalities are important genetic etiology of spermatogenic failure in Chinese population and it is essential to screen them during diagnosis of male infertility before in vitro assisted fertilization by introcytoplasmic sperm injection.
染色体异常和Y染色体微缺失被认为是白种人群中与精子发生失败相关的两个常见遗传原因。为了研究这两种遗传缺陷在中国无精子症或严重少精子症患者中的分布情况，对358例特发性不育男性进行了G显带核型分析，其中包括256例无精子症患者和102例严重少精子症患者，并对那些未检测到染色体异常的患者和100例生育力正常的对照者进行了多重PCR法Y染色体AZF区域微缺失筛查。在358例患者中，39例（10.9%）被发现存在染色体异常，其中克兰费尔特综合征（47, XXY）是最常见的染色体畸变。无精子症患者中性染色体异常的发生率显著高于严重少精子症患者（12.1%对1%）。在其余319例核型正常的患者中，46例（14.4%）被发现存在AZF区域微缺失。无精子症患者和严重少精子症患者中AZF微缺失的患病率分别为15%和13.1%。AZFc区域的微缺失最为常见，所有AZFa区域的微缺失均见于无精子症患者。在生育力正常的对照者中未检测到AZF区域微缺失。总之，染色体异常和Y染色体AZF区域微缺失可能占中国无精子症或严重少精子症不育患者的25%左右，提示这两种异常是中国人群精子发生失败的重要遗传病因，在男性不育诊断过程中，在进行卵胞浆内单精子注射体外辅助受精之前对其进行筛查至关重要。
