罕见的8p部分缺失伴重复患儿1例的临床及遗传学分析

Prenatal diagnosis and genetic analysis of a rare case with 8p deletion and duplication

目的明确1例智力低下、语言发育迟缓及自闭症患儿的遗传学病因。方法选取2019年6月30日于泉州市妇幼保健院就诊的1例罕见8p部分缺失伴重复患儿为研究对象。采集患儿及其父母的外周血样,进行G显带染色体核型分析以及单核苷酸多态性微阵列(SNP-array)检测。结果患儿核型为46,XX,dup(8p?),其父母均未见明显异常。SNP-array检测显示患儿染色体8p23.3p23.1区存在6.8 Mb的片段缺失,8p23.1p12区存在21.8 Mb的片段重复,上述拷贝数变异均为新发,并判断为致病变异。结论患儿的临床表型与染色体8p部分缺失重复相关,SNP-array检测对智力低下的患儿的诊断具有一定的价值。

Objective To explore the genetic etiology for a child featuring mental retardation,language delay and autism.Methods G-banding chromosomal karyotyping and single nucleotide polymorphism array(SNP-array)were carried out for the child and her parents.Results The child was found to have a 46,XX,dup(8p?)karyotype,for which both of her parents were normal.SNP-array revealed that the child has harbored a 6.8 Mb deletion in 8p23.3p23.1 and a 21.8 Mb duplication in 8p23.1p12,both of which were verified as de novo pathogenic copy number variants.Conclusion The clinical features of the child may be attributed to the 8p deletion and duplication.SNP-array can facilitate genetic diagnosis for children featuring mental retardation in conjunct with other developmental anomalies.