摘要目的 应用染色体微阵列(chromosomal microarray analysis,CMA)技术对1例不明原因的全面性发育迟缓患儿进行分析.方法 应用基于单核苷酸多态性的CMA技术对患儿进行拷贝数变异分析,用荧光定量PCR验证结果.结果 患儿全基因组CMA检测发现染色体2q22.3q23.3区域存在约2.5Mb的重复(hg19:148 680 762～151 210 898),涉及ACVR2A、KIF5C、MBD5、EPC2、LYPD6、LYPD6B、MMADHC以及ORC4等8个基因.其中MBD5可能是引起患儿表型的关键基因.结论 2q23重复是引起该患儿全面性发育迟缓的关键因素,该区域包含的MBD5基因可能是引起2q23主要临床表型的关键基因.

abstractsObjective To carry out single nucleotide polymorphism (SNP)-based chromosome microarray analysis (CMA) for a boy featuring global developmental delay.Methods The SNP array was conducted for a child,and real-time PCR was used to validate its result and identify the origin of pathological copy number variants.Results SNP array revealed that the patient carried a de novo 2.5 Mb duplication at 2q22.3q23.3,which encompassed ACVR2A,KIF5C,MBD5,EPC2,LYPD6,LYPD6,MMADHC and ORC4 genes.Literature review suggested that the MBD5 gene from the duplicated region may have predisposed to the global developmental delay.Conclusion The patient's clinical phenotype was consistent to that of 2q23 duplication,for which the MBD5 gene may play a key role.CMA has provided a very important tool for the diagnosis of patients with global developmental delay.