Genetic Association Analysis of Fasting and 1- and 2-Hour Glucose Tolerance Test Data Using a Generalized Index of Dissimilarity Measure for the Korean Population.
Glucose tolerance tests have been devised to determine the speed of blood glucose clearance. Diabetes is often tested with the standard oral glucose tolerance test (OGTT), along with fasting glucose level. However, no single test may be sufficient for the diagnosis, and the World Health Organization (WHO)/International Diabetes Federation (IDF) has suggested composite criteria. Accordingly, a single multi-class trait was constructed with three of the fasting phenotypes and 1- and 2-hour OGTT phenotypes from the Korean Association Resource (KARE) project, and the genetic association was investigated. All of the 18 possible combinations made out of the 3 sets of classification for the individual phenotypes were taken into our analysis. These were possible due to a method that was recently developed by us for estimating genomic associations using a generalized index of dissimilarity. Eight single-nucleotide polymorphisms (SNPs) that were found to have the strongest main effect are reported with the corresponding genes. Four of them conform to previous reports, located in theCDKAL1gene, while the other 4 SNPs are new findings. Two-order interacting SNP pairs of are also presented. One pair (rs2328549 and rs6486740) has a prominent association, where the two single-nucleotide polymorphism locations areCDKAL1andGLT1D1. The latter has not been found to have a strong main effect. New findings may result from the proper construction and analysis of a composite trait.
Department of Physiology and Biophysics, Eulji University, Daejeon 35233, Korea.
Jaeyong
J
Yee
Department of Statistics, Seoul National University, Seoul 08826, Korea.
Yongkang
Y
Kim
Department of Statistics, Seoul National University, Seoul 08826, Korea.
Taesung
T
Park
Department of Preventive Medicine, Eulji University, Daejeon 34824, Korea.
Mira
M
Park
gene-gene interaction; genome wide association; glucose tolerance test