Abstract： Objective To probe the role of the glucagon receptor (GCG R) gene in the background of type 2 diabetes mellitus in Chinese.Methods A total of 200 unrelated Chinese subjects (120 patients with type 2 diabetes and 80 nondiabetic control individuals without family history of diabetes) from Kunming were screened for the presence of the polymorphic variants in codon domains of the GCG R gene by use of polymerase chain reaction denaturing gradient gel electrophoresis (PCR DGGE).Results Only a heterozygous polymorphic band was observed in exon 7 in 2 diabetics and 1 control person and no differences in the frequencies of this abnormal conformer were found between diabetic patients and control group.No other abnormal band patterns in codon regions of the GCG R gene were showed in all of the subjects investigated,including type 2 diabetics and controls.Conclusion The results suggested that the GCG R gene is not the causative gene responsible for the occurrence of type 2 diabetes mellitus in Chinese and indicated the genetic heterogeneity of type 2 diabetes mellitus in different ethnic populations.