title: Genetic polymorphism PC-1 K121Q and ethnic susceptibility to insulin resistance.
abstract: Genetic susceptibility may be responsible for high prevalence of insulin resistance in Asian Indians. This study was carried out in samples of local Asian Indians and Caucasians to determine whether plasma cell membrane glycoprotein (PC)-1 K121Q and insulin receptor substrate-1 (IRS-1) G972A polymorphisms contribute significantly to susceptibility to insulin resistance in Asian Indians. The frequency of carrying at least one copy of the PC-1 121Q variant in Asian Indians was significantly higher than that in Caucasians (P = 0.01), but the frequency was similar for IRS-1 972A (6% and 7%). A significantly higher insulin area under the curve during oral glucose tolerance testing (P < 0.0001) and lower insulin sensitivity during hyperinsulinemic-euglycemic clamps (P = 0.04) were found in Asian Indians with PC-1 121Q variant compared with Asian Indians with wild-type PC-1 and with Caucasians with or without the polymorphism. IRS-1 972A was not associated with any change in insulin sensitivity. We conclude that the PC-1 K121Q polymorphism associates with primary insulin resistance in migrant Asian Indians. A relatively high frequency of this polymorphism thus may be one factor contributing to insulin resistance susceptibility in Asian Indians. This finding indicates the need for expanded studies on the association between PC-1 K121Q and insulin resistance in a representative sample of the Asian Indian population.
authors.affiliation: Center for Human Nutrition and the Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA. nicola.abate@utsouthwestern.edu
authors.forename: Nicola
authors.initials: N
authors.lastname: Abate
authors.forename: Lucia
authors.initials: L
authors.lastname: Carulli
authors.forename: Alberto
authors.initials: A
authors.lastname: Cabo-Chan
authors.forename: Manisha
authors.initials: M
authors.lastname: Chandalia
authors.forename: Peter G
authors.initials: PG
authors.lastname: Snell
authors.forename: Scott M
authors.initials: SM
authors.lastname: Grundy
mesh_terms: D000328:Adult; D044466:Asian People / Q000235:genetics*; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D015309:Glucose Clamp Technique; D005951:Glucose Tolerance Test; D005973:Glutamine / Q000235:genetics; D006801:Humans; D006946:Hyperinsulinism / Q000097:blood; D007194:India; D007333:Insulin Resistance / Q000235:genetics*; D008239:Lysine / Q000235:genetics; D008297:Male; D008875:Middle Aged; D010727:Phosphoric Diester Hydrolases / Q000235:genetics*; D011110:Polymorphism, Genetic; D011755:Pyrophosphatases / Q000235:genetics*; D044465:White People / Q000235:genetics
chemical_list: D005973:Glutamine; D010727:Phosphoric Diester Hydrolases; C065962:ectonucleotide pyrophosphatase phosphodiesterase 1; D011755:Pyrophosphatases; D008239:Lysine