Analysis Of A Family With MODY Caused By A Mutation In The INS Gene

Objective:Maturity onset diabetes of the young(MODY)is a special types of diabetes mellitus caused by monogenic mutations.14 MODY subtypes have been listed in the Online Mendelian Inheritance in Man(OMIM)database.In this study,we collected clinical manifestation and sequenced genes of a Chinese family with suspected MODY,in order to detect the unknown mutation gene site.Methods: We collected the medical history,physical,laboratory findings of the family.Then we completed the gene sequencing of the proband to determine the mutation by a High-throughput sequencing technology and confirmed the results in his parents by using Sanger sequencing.SWISS-MODEL software was used to predict the impact of the mutation on protein function and structure.Results: The family consisted of 15 members from 3 generations.The proband presented with polydipsia,polyuria,polyphagia,and weight loss leading to the diagnosis of diabetes mellitus.His mother was diabetic,his younger brother and uncle were confirmed to have diabetes after examination.A novel heterozygous mutation(c.220G>A;p.A74T)in theINS gene was found and confirmed in his parents that his mother carries the mutation gene,and his father has no genetic mutation in this site.Conclusion: We collected a family with MODY,and a novel mutation on INS gene was found by gene testing.And these results expand the gene spectrum.However,the pathogenic mechanism is not clear yet,and further function research is needed.