Researchers led by the University of North Carolina, Chapel Hill's Karen Mohlke report on analyzing exome array data to find new loci and low-frequency variants associated with insulin processing and secretion in Nature Genetics this week. Mohlke and her colleagues drew on data obtained using the Illumina HumanExome Beadchip from 8,229 Finnish men who did not have diabetes. From this, they found novel low-frequency variants in BC1D30, KANK1, and PAM that were associated with fasting proinsulin or insulinogenic index. They also noted variants SGSM2 and MADD that were linked to fasting proinsulin concentrations.
"Although sequencing will still be required to completely assess variants associated with insulin processing, secretion and glycemic traits," the researchers write, "this study provides proof of principle that exome array genotyping is a powerful approach to identify low-frequency functional variants and fine map GWAS-identified loci in complex traits."