Maturity-onset diabetes of the young (MODY) is a distinct class of diabetes mellitus characterized by a heterogeneous group of monogenic disorders caused by genetic defects primarily affecting insulin secretion, synthesis, or action mechanisms, accounting for 1%-5% of diabetic patients. It is the most common form of monogenic diabetes. This article reports a case of diabetes diagnosed in the Department of Endocrinology and Metabolism Diseases, First Affiliated Hospital of Anhui Medical University. Genetic testing revealed a mutation in the hepatocyte nuclear factor 4α(HNF4A) gene, specifically c.334 (exon4)C>T(p.Arg112Trp), leading to a definitive diagnosis of MODY1. The diagnostic and treatment process of this case is described, along with a review of relevant literature. Given the low prevalence of MODY1, this report of a family case expands the spectrum of known HNF4A gene mutations, which may enhance clinicians' understanding of the disease. This, in turn, can promote precise diagnosis, classification, and treatment of MODY.

青少年起病的成人型糖尿病（MODY）是一组由胰岛素分泌、合成或作用等相关基因缺陷引起的一类特殊类型糖尿病，占糖尿病患者的1%~5%，是最常见的单基因糖尿病。本文报道了1例就诊于安徽医科大学第一附属医院内分泌代谢科的糖尿病患者，经基因检测证实为肝细胞核因子4α（HNF4A）基因c.334（exon4）C>T（p.Arg112Trp）突变所致，从而明确诊断MODY1的诊治过程并复习相关文献。由于MODY1患病率低，此次报道该家系扩展了MODY1的基因突变谱，有助于提高临床医生对该病的认识，从而促进对MODY的精准诊断，精准分型和精准治疗。