title: Genomic scan of glucose and insulin metabolism phenotypes: the HERITAGE Family Study.
abstract: Genetic factors play a role in the regulation of glucose metabolism-related traits such as insulin sensitivity (S(I)), insulin secretion, and glucose effectiveness (S(G)). Several genomic scans have been performed to localize genes involved in glucose metabolism-related traits. However, few of these studies have been performed with phenotypes derived from the frequently sampled intravenous glucose tolerance test (IVGTT) using the minimal modeling (MINMOD) approach. Here, we report on such a scan for glucose metabolism-related traits derived from MINMOD analysis of IVGTT data in 322 sibling pairs from 95 sedentary white families and 75 sibling pairs from 49 sedentary black families from the HERITAGE Family Study. In addition to S(I) and S(G), we also considered acute insulin response to a glucose challenge (AIR(Glucose)), which is an index for insulin secretion, and disposition index (DI, product of S(I) and AIR(Glucose)), which is a measure of the activity of pancreatic beta cells corrected for insulin resistance. These traits were adjusted for age, sex, and body mass index (BMI) in each of 8 sex-by-generation-by-race groups, and then standardized residuals were used as the phenotypes in the linkage analyses. Analyses were with the multipoint variance components linkage method, as implemented in the computer program SEGPATH, using 509 markers. Several regions with promising linkages (LOD score >/= 1.75, P </=.0023) were detected. They include five regions (1q41 and 8p23.2 for S(I), 4q32.1 and 10p15.3 for AIR(Glucose), and 13q32.1 for DI) in whites and 2 regions (9p11.2 for S(G) and 10q26.11 for S(I)) in blacks. Three of these regions (4q32.1, 9p11.2, 10p15.3) are likely to harbor genes that influence interindividual variation in glucose metabolism-related traits as they replicate findings from other studies. Fine mapping and association studies of candidate genes within these genomic regions are warranted.
authors.affiliation: Division of Biostatistics, and the Department of Genetics, Washington University School of Medicine, St Louis, MO 63110, USA.
authors.forename: Ping
authors.initials: P
authors.lastname: An
authors.forename: Yuling
authors.initials: Y
authors.lastname: Hong
authors.forename: S John
authors.initials: SJ
authors.lastname: Weisnagel
authors.forename: Treva
authors.initials: T
authors.lastname: Rice
authors.forename: Tuomo
authors.initials: T
authors.lastname: Rankinen
authors.forename: Arthur S
authors.initials: AS
authors.lastname: Leon
authors.forename: James S
authors.initials: JS
authors.lastname: Skinner
authors.forename: Jack H
authors.initials: JH
authors.lastname: Wilmore
authors.forename: Yvon C
authors.initials: YC
authors.lastname: Chagnon
authors.forename: Richard N
authors.initials: RN
authors.lastname: Bergman
authors.forename: Claude
authors.initials: C
authors.lastname: Bouchard
authors.forename: D C
authors.initials: DC
authors.lastname: Rao
mesh_terms: D000293:Adolescent; D000328:Adult; D044383:Black People / Q000235:genetics; D015992:Body Mass Index; D005260:Female; D008040:Genetic Linkage; D005819:Genetic Markers; D015894:Genome, Human; D005947:Glucose / Q000378:metabolism*; D005951:Glucose Tolerance Test; D006801:Humans; D007328:Insulin / Q000378:metabolism*; D008126:Lod Score; D008297:Male; D018895:Microsatellite Repeats; D008875:Middle Aged; D010641:Phenotype; D020641:Polymorphism, Single Nucleotide; D040641:Quantitative Trait Loci; D044465:White People / Q000235:genetics
chemical_list: D005819:Genetic Markers; D007328:Insulin; D005947:Glucose