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.
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.


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.
Baier
L J
LJ
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
Permana
P A
PA
Traurig
M
M
Dobberfuhl
A
A
Wiedrich
C
C
Sutherland
J
J
Thuillez
P
P
Luczy-Bachman
G
G
Hara
M
M
Horikawa
Y
Y
Hinokio
Y
Y
Hanson
R L
RL
Bogardus
C
C
D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D001130:Arizona; D051778:Basic Helix-Loop-Helix Leucine Zipper Transcription Factors; D003062:Codon; D004268:DNA-Binding Proteins / Q000235:genetics*; D003924:Diabetes Mellitus, Type 2 / Q000235:genetics*; D019281:Dimerization; D005006:Ethnicity / Q000235:genetics*; D005091:Exons; D051537:Hepatocyte Nuclear Factor 1; D051538:Hepatocyte Nuclear Factor 1-alpha; D051539:Hepatocyte Nuclear Factor 1-beta; D051542:Hepatocyte Nuclear Factor 3-beta; D051557:Hepatocyte Nuclear Factor 4; D018398:Homeodomain Proteins; D006801:Humans; D007198:Indians, North American / Q000235:genetics*; D009154:Mutation; D009687:Nuclear Proteins / Q000235:genetics*; D010750:Phosphoproteins / Q000235:genetics*; D011110:Polymorphism, Genetic; D015534:Trans-Activators / Q000235:genetics*; D014157:Transcription Factors / Q000737:chemistry / Q000235:genetics*
D051778:Basic Helix-Loop-Helix Leucine Zipper Transcription Factors; D003062:Codon; D004268:DNA-Binding Proteins; C496502:FOXA2 protein, human; C496487:HNF1A protein, human; C496495:HNF1B protein, human; C496592:HNF4A protein, human; D051538:Hepatocyte Nuclear Factor 1-alpha; D051557:Hepatocyte Nuclear Factor 4; D018398:Homeodomain Proteins; C403128:MLX protein, human; D009687:Nuclear Proteins; D010750:Phosphoproteins; D015534:Trans-Activators; D014157:Transcription Factors; C084010:pancreatic and duodenal homeobox 1 protein; D051537:Hepatocyte Nuclear Factor 1; D051542:Hepatocyte Nuclear Factor 3-beta; D051539:Hepatocyte Nuclear Factor 1-beta