目的:报告一例Y染色体大部分缺失的无精症患者,并应用遗传物理图谱对Y染色体断裂位点进行定位,探导Y染色体异常与无精症的关系。方法:采用G显带、多重PCR技术对患者进行染色体核型分析、Y染色体微缺失检测。结果:患者染色体核型为46,X,del(Y)(q11.2),Y染色体微缺失检测的15个序列标签位点中,只有AZFa区SY82、SY84、SY86和AZFb区SY124、SY127、SY128扩增。根据遗传物理图谱推断断裂位点为Y q11.23。结论:Y染色体大部分缺失是引起该患者无精的原因。 OBJECTIVE: To report a case of azoospermia in which most of the Y chromosome is absent, and to map the site of Y chromosome rupture using genetic mapping to explore the relationship between Y chromosome abnormality and azoospermia. Methods: G - banding and multiplex PCR were used to analyze the karyotypes and Y - chromosome microdeletions. Results: The chromosome karyotype was 46, X, del (Y) (q11.2). Among the 15 sequence tags detected by Y chromosome microdeletion, only SY82, SY84, SY86 in AZFa region and SY124, SY128 amplification. According to the genetic map infer the fracture site Y q11.23. Conclusion: The majority of Y chromosome loss is the cause of the patient’s azoospermia.