Abstract: Objective To find novel genes related to maturity-onset diabetes of the young（MODY）or novel mutations of known MODY related genes and provide the basis for MODY diagnosis. Methods Taking the known clinical features of MODY as screening criteria, we choose four patients from the Endocrine Department of Peking Union Medical College Hospital and extract their genomic DNA for whole exome sequencing. PCR and Sanger sequencing are used to validate the sequencing results. Results Two novel mutations of the GCK gene and HNF4α gene, c.1348G>T（p.Ala450Thr）and c.758G>A（p.Arg253Gln）were found in two patients. Conclusions These two patients are both MODY patients and this is the first time the novel mutations were found.

Key words: Key words：MODY, GCK, HNF4α, mutation