摘要目的 分析1例发育迟缓、智力低下女童的遗传学发病机制,为其家系的遗传咨询提供依据.方法 常规G显带分析患儿及其父母的外周血染色体核型,微阵列比较基因组杂交(array comparative genomic hybridization,aCGH)技术对患儿及其父母染色体片段重复/缺失进行分析.结果 G显带分析患儿及其父母染色体核型均未见异常.aCGH检测结果显示患儿染色体17p11.2区存在3.37 Mb杂合缺失,其父母未检测到染色体微重复/微缺失,患儿该区微缺失为新发变异.结论 患儿诊断为Smith-Magenis综合征,RAI1基因可能是该综合征的关键基因.

abstractsObjective To explore the molecular mechanism of a girl with developmental delay and intellectual disability.Methods Chromosomal karotypes of the child and her parents were analyzed with routine G-banding method. Their genomic DNA was also analyzed with array comparative genomic hybridization (aCGH )for chromosomal duplications/deletions.Results No karyotypic abnormality was detected in the child and her parents,while aCGH has identified a de novo 3.37 Mb deletion at 17p11.2 in the child.Conclusion The child was diagnosed with Smith-Magenis syndrome,for which RAI1 may be the causative gene.