SERAC1基因变异致MEGDEL综合征2例并文献回顾

Two cases of MEGDEL syndrome due to variants of SERAC1 gene and a literature review

目的探讨2例SERAC1基因变异所致的MEGDEL综合征患儿的临床表型及遗传学特点。方法以2020年7月14日与2018年7月28日就诊于福建医科大学附属协和医院儿科的2例MEGDEL综合征患儿作为研究对象。回顾分析患儿的临床资料及基因检测结果,并对MEGDEL综合征进行文献回顾。结果2例患儿均存在精神运动发育迟滞、肌张力障碍、感音神经性耳聋,尿3-甲基戊烯二酸升高,头颅MRI显示Leigh样综合征改变。全外显子组测序显示二者均携带致病性SERAC1基因复合杂合变异,分别为c.1159C>T、c.442C>T和c.1168C>T、第4~9外显子杂合缺失。结论SERAC1基因变异所致的MEGDEL综合征患儿临床表现多样,掌握其临床特点和典型的影像学改变将有助于提高临床诊治水平。尿有机酸检测联合基因变异分析有助于该病的早期诊断。上述发现丰富了SERAC1基因的变异谱。

Objective To explore the clinical phenotype and genetic features of two children with MEGDEL syndrome due to variants of the SERAC1 gene.Methods Two children who had presented at the Fujian Medical University Union Hospital respectively on July 14,2020 and July 28,2018 were selected as the study subjects.Clinical features and results of genetic testing were retrospectively analyzed.Results Both children had featured developmental delay,dystonia and sensorineural deafness,along with increased urine 3-methylglutaric acid levels.Magnetic resonance imaging revealed changes similar to Leigh-like syndrome.Gene sequencing revealed that both children have harbored pathogenic compound heterozygous variants of the SERAC1 gene,including c.1159C>T and c.442C>T in child 1,and c.1168C>T and exons 4~9 deletion in child 2.Conclusion Children with MEGDEL syndrome due to SERAC1 gene variants have variable clinical genotypes.Delineation of its clinical characteristics and typical imaging changes can facilitate early diagnosis and treatment.Discovery of the novel variants has also enriched the spectrum of SERAC1 gene variants.