一例染色体14q部分缺失患儿的临床表型及遗传学分析

Phenotypic and genetic analysis of a child featuring multiple malformations due to chromosome 14q deletion

目的分析1例智力低下、生长发育迟缓及语言发育障碍患儿的遗传学病因。方法用G显带技术分析患儿及其父母的外周血染色体，用微阵列比较基因组杂交技术（array comparative hybridization，array-CGH）分析患儿及其父母的DNA拷贝数，并对缺失区及其上下游短串联重复（short tandem repeats，STRs）位点进行检测，对aCGH的结果进行验证，经数据库比对和文献分析以明确异常缺失区的病理意义。结果患儿父母外周血染色体核型分析结果未见异常。患儿核型为46，XX，t（8；14）（q24．1；q13）。aCGH检测发现染色体14q22．1区存在2．9Mb的新发缺失。结论染色体14q22．1区微缺失可能与患儿智力低下、生长发育迟缓及语言发育迟缓等表型相关。

Objective To analyze a child with mental retardation, growth retardation and language development disorders. Methods Conventional G-banding analysis was performed on chromosomes cultivated from peripheral blood samples derived from the child and her parents. Array-comparative genomic hybridization （aCGH） was performed to detect minor structural chromosomal abnormalities, and the result was confirmed by short tandem repeats （STR） analysis. Results For the child and her parents, no karyotypic abnormality was detected. However, aCGH analysis has identified a 14@2. 1 deletion in the child. The mierodeletion, with a size of 2.9 Mb was confirmed by STR analysis. Conclusion The 2.9 Mb chromosomal microdeletion probably underlies the mental retardation, growth retardation and language development disorders in the child.