三例谷氨酸脱氢酶型先天性高胰岛素血症患儿的GLUD1基因突变分析

Mutation analysis of the GLUD1 gene in patients with glutamate dehydrogenase congenital hyperinsulinism

目的 对3例临床诊断为谷氨酸脱氢酶型先天性高胰岛素血症的患儿家系进行遗传学分析并对中国儿童谷氨酸脱氢酶型先天性高胰岛素血症的遗传发病机制进行初步探讨.方法 选取3例临床诊断为谷氨酸脱氢酶型先天性高胰岛素血症患儿的家系,应用PCR-DNA直接测序技术对3例患儿家系谷氨酸脱氢酶1基因（glutamate dehydrogenase 1,GLUD1）第6,7,10,11,12外显子区进行测序分析.结果 第1例患儿及其父亲GLUD1基因第7外显子区发现了1个R269H杂合突变,遗传方式为常染色体显性遗传.第2例患者GLUD1基因的第11外显子区发现了1个S445L杂合突变,为新生突变.第3例患儿家系GLUD1基因第6,7,10,11,12外显子均未发现突变.结论 在某些中国人中,谷氨酸脱氢酶基因R269H,S445L杂合突变可以导致谷氨酸脱氢酶型先天性高胰岛素血症的发生.

Objective To investigate the glutamate dehydrogenase 1 （GLUD1） gene mutation of three patients diagnosed as glutamate dehydrogenase congenital hyperinsulinism （GDH-HI）. Methods Three patients diagnosed as GDH-HI and their parents were involved in the study. PCR-DNA direct sequencing was used to analyze the exons 6,7,10,11 and 12 of theGLUD1 gene. Results In the first case, an R269H heterozygous mutation was found in the GLUD1 gene, with autosomal dominant inheritance. In the second case, there was a de novo S445L heterozygous mutation of the GLUD1 gene. No mutation was detected in the third case. Conclusion In Chinese, R269H, S445L heterozygous mutation of the GLUD1 gene can lead to GDH-HI. Genetic analysis is necessary in making genetic diagnosis of congenital hyperinsulinsm.