SLC9A7基因变异所致X连锁精神发育迟滞1例患儿的临床特征及遗传学分析

Clinical and genetic analysis of a child with X-linked mental retardation due to variant of SLC9A7 gene

目的:对1例临床表现为智力低下、语言及运动发育落后、癫痫的患儿进行临床和遗传学分析。方法:以1例因"间断抽搐2个月"为代主诉于2020年3月就诊于郑州大学第一附属医院儿科的患儿为研究对象。收集患儿的临床资料,采集患儿及其父母的外周血样进行高通量测序,对候选变异进行Sanger测序家系验证及生物信息学分析。结果:患儿表现为智力低下、语言及运动发育迟缓、癫痫发作。高通量测序结果显示其SLC9A7基因上存在半合剪接位点变异(NM_032591.3:c.1030-1G>C),遗传自母亲,既往未见报道。结论:SLC9A7基因半合剪接位点变异(c.1030-1G>C)可能是该患儿的遗传学病因。

Objective To explore the clinical and genetic characteristics of a child with mental retardation,language and motor developmental delay and epilepsy.Methods A Child who was admitted to the First Affiliated Hospital of Zhengzhou University in March 2020 for intermittent seizures for over two months was Selected as the study subject.Clinical data of the child was collected.Peripheral blood samples of the child and his parents were collected and subjected to high throughput sequencing.Candidate variants were verified by Sanger sequencing and bioinformatic analysis.Results The clinical manifestations of the child have included mental retardation,language and motor developmental delay,and seizures.High-throughput sequencing revealed that he has harbored a hemizygous splice site variant(NM_032591.3:c.1030-1G>C)of the SLC9A7 gene,which was inherited from his mother and unreported previously.Conclusion The hemizygous splice site variant(NM_032591.3:c.1030-1G>C)of the SLC9A7 gene probably underlay the disease in this child.Above finding has provided a basis for clinical diagnosis and genetic counseling.