Genetic variation screening and association studies of the adenylate cyclase activating polypeptide 1 (ADCYAP1) gene in patients with type 2 diabetes

Adenylate cyclase activating polypeptide 1 (ADCYAP1) is a pancreatic neuropeptide and modulates glucose-stimulated insulin secretion. The ADCYAP1 gene is located on chromosome 18p11 linked to type 2 diabetes. To test whether it is a candidate gene for type 2 diabetes, screening of the gene in Finnish and Swedish type 2 diabetic patients was done. Two novel SNPs, g.9863G>A (G54D) in exon 3 and g.12712C>G in the 3'-UTR of exon 5 of the ADCYAP1 gene (accession number X60435), were found. PCR-RFLP genotyping was then performed in a total of 253 type 2 diabetic patients and 253 non-diabetic control subjects. Transmission disequilibrium test (TDT) was performed in 132 parent-offspring trios. The G allele frequencies of g.9863G>A (G54D) and g.12712C>G of the ADCYAP1 gene were higher in type 2 diabetic patients than in non-diabetic control subjects (21.0% vs 15.8%, P=0.04; 5.3% vs 3.0%, P=0.045). However, no significant differences in clinical variables was seen between the different genotype carriers, and also no transmission distortion of the G allele of SNP g.9863G>A (G54D) was observed in 132 parent-offspring trios. The present study thus suggest that the variants in the ADCYAP1 gene may not be major influence of the susceptibility to type 2 diabetes in Finnish and Swedish Caucasians.