Diabetes Care, Vol 23, Issue 3 302-304, Copyright © 2000 by American Diabetes Association
Mutations in the genes for hepatocyte nuclear factor (HNF)-1alpha, -4alpha, -1beta, and -3beta; the dimerization cofactor of HNF-1; and insulin promoter factor 1 are not common causes of early-onset type 2 diabetes in Pima Indians
LJ Baier, PA Permana, M Traurig, A Dobberfuhl, C Wiedrich, J Sutherland, P Thuillez, G Luczy-Bachman, M Hara, Y Horikawa, Y Hinokio, RL Hanson and C Bogardus
Phoenix Epidemiology and Clinical Research Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Arizona 85016, USA. lbaier@phx.niddk.nih.gov
OBJECTIVE: Maturity-onset diabetes of the young (MODY) is a genetically
heterogeneous subtype of type 2 diabetes characterized by an early age at
onset and autosomal dominant inheritance. MODY can result from heterozygous
mutations in at least five genes. The purpose of this study was to
determine whether alterations in known MODY genes and two MODY candidate
genes contribute to the development of early-onset type 2 diabetes in Pima
Indians. RESEARCH DESIGN AND METHODS: The coding regions of the known MODY
genes hepatocyte nuclear factor (HNF)-1alpha, HNF-4alpha, HNF-1beta, and
insulin promoter factor 1 and the coding regions of two MODY candidate
genes, HNF-3beta and the dimerization cofactor of HNF-1, were sequenced in
genomic DNA from Pima Indians. The primary "affected" study population
consisted of 46 Pima Indians whose age at onset of type 2 diabetes was <
or =20 years. DNA sequence variants identified in the affected group were
then analyzed in a group of 80 "unaffected" Pima Indians who were at least
40 years old and had normal glucose tolerance. RESULTS: A total of 11
polymorphisms were detected in these genes. However, none of the
polymorphisms differed in frequency among Pima Indians with an early age at
onset of diabetes compared with older Pima Indians with normal glucose
tolerance. CONCLUSIONS: Mutations in these known MODY or MODY candidate
genes are not a common cause of early-onset diabetes in Pima Indians.