4例SRY阳性的46,XX男性综合征患者临床及细胞分子遗传学研究

目的:探讨SRY阳性的46,XX男性综合征患者的临床及细胞分子遗传学特征。方法:分析4例SRY阳性的46,XX男性综合征患者的临床特点,并进行染色体核型分析、荧光原位杂交(FISH)、SRY基因检测、Y染色体微缺失等细胞和分子遗传学检测。结果:4例患者社会性别均为男性,身材低于正常男性均值。均因不育就诊,双侧睾丸体积小、质地软,精液检查均为无精子症。阴茎发育正常。性激素检查示高促性腺激素性性腺功能不全。染色体核型均为46,XX,Y染色体微缺失检测示AZFa,b,c区域均缺失。SRY基因均存在,FISH结果3例患者显示SRY基因易位于X染色体短臂。结论:SRY阳性的46,XX男性综合征患者常为男性表型,但睾丸发育不良,多伴有身材矮小和不育。患者的男性表型是由于基因组中存在SRY基因。无精子表型是由于缺失AZF。Y染色体长臂上可能存在与身高相关的基因。深入进行细胞、分子遗传学研究有助于揭示46,XX男性综合征基因型-表型的关系。

Clinical,Molecular and Cytogenetic Studies on 4 Patients with 46,XX (SRY Positive) Male Syndrome

OBJECTIVE: To analyze the clinical, molecular and cytogenetic features of 46, XX (SRY positive) male syndrome. METHODS: The clinical features of 4 patients with 46, XX (SRY positive) male syndrome were analyzed retrospectively. Karyotyping, FISH, PCR amplification of the SRY gene, and Y-chromosome microdeletion were performed to study their molecular cytogenetic features. RESULTS: The Four patients were all sociopsychologically males of short stature and came to hospital for infertility. Physical examination revealed that their testes were small in volume and soft in texture, but their penes were normal. Semen analyses showed complete azoospermia. Detection of serum sexual hormone suggested hypergonadotropic hypogonadism. All were karyotyped as 46, XX. Molecular analyses revealed the presence of the SRY gene and absence of AZFa, b and c of the Y chromosome. FISH analysis showed that SRY genes were translocated to Xp in 3 of the patients. CONCLUSION: Phenotypically 46, XX (SRY positive) male patients are males generally, for the presence of the SRY gene in the whole genome and azoospermia due to the deletion of AZF. The clinical characteristics of the patient include testis dysgenesis, infertility and short stature. The long arm of the Y chromosome might contain the gene associated with body height. Extensive molecular and cytogenetic studies on 46, XX male syndrome may help to elucidate its genotype-phenotype relation.