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目的:对1例临床表征为身材矮小、鼻根部内陷、双侧隐睾、智力低下患儿进行遗传学分析，探讨该染色体结构异常与临床表征之间的关系。方法:应用G显带染色体核型分析及染色体微阵列分析(chromosomal microarray analysis，CMA)技术对患儿进行遗传学检测，并对其父母进行外周血染色体核型分析。结果:G显带分析结果显示患儿染色体核型为46，Y，der(X)t(X；Y)(p22；q11)，mat。CMA检测结果提示患儿X染色体短臂Xp22.33p22.31存在约8.3 Mb片段缺失，Y染色体长臂Yq11.221qter存在约43.3 Mb片段重复。其父亲染色体核型正常，母亲染色体核型结果为46，X，der(X)t(X；Y)(p22；q11)。结论:患儿携带母源性der(X)t(X；Y)(p22；q11)染色体非平衡易位，携带者的表型与其性别以及X染色体缺失片段的大小和位置密切相关。男性携带者智力障碍、生长发育落后等异常表型较女性更为严重。“,”Objective:To explore the genetic basis for a child featuring short stature, saddle nose, cryptorchidism and mental retardation.Methods:The child and his parents were subjected to G-banded karyotyping and chromosomal microarray analysis (CMA).Results:The child was found to have a 46, Y, der(X)t(X; Y)(p22; q11) mat karyotype. CMA revealed a 8.3 Mb deletion at Xp22.33p22.31 and a 43.3 Mb duplication at Yq11.221qter. His mother had a karyotype of 46, X, der(X)t(X; Y)(p22; q11). His father had a normal karyotype.Conclusion:The child has carried an unbalanced translocation der(X)t(X; Y)(p22; q11)derived from his mother. His clinical phenotype has correlated with the size and position of X chromosome deletion. Compared with the females, abnormal phenotypes such as mental retardation and growth retardation of male carriers are more severe.