Mutations in the insulin promoter factor-1 gene in late-onset type 2 diabetes mellitus.
OBJECTIVE
Insulin promoter factor-1 (IPF-1) is a transcription factor expressed in pancreatic beta cells. Following the identification of missense variants in the coding regions of the IPF-1 gene, in subjects selected for a strong family history of type 2 diabetes, the aim of our study was to evaluate the prevalence of these variants in the common form of type 2 diabetes.


METHODS
Three variants (C18R, Q59L and D76N) were screened by PCR-RFLP in a group of 296 unrelated French late-onset type 2 diabetic subjects consecutively recruited in a diabetes department of a university hospital, regardless of family history of diabetes.


RESULTS
The C18R and Q59L variants were each found in 0.37% of the diabetic patients, and in none of 147 controls. We did not detect the D76N variant, which was the most frequent variant in subjects with a strong family history of diabetes, in patients or controls.


CONCLUSIONS
We have observed a combined prevalence of missense variants in the coding region of the IPF-1 gene of around 1%, in unselected patients with the common form of late-onset type 2 diabetes. The prevalence of these variants in subjects with a strong family history of type 2 diabetes had been found to be as high as approximately 6%. These differences in prevalence might be related to differences in the clinical profile of patients, such as age of onset of diabetes and associated obesity, as well as a family history of diabetes.
Reis
A F
AF
INSERM Unité 342, Institut Cochin de Gënëtique Molëculaire, Paris, France.
Ye
W Z
WZ
Dubois-Laforgue
D
D
Bellanné-Chantelot
C
C
Timsit
J
J
Velho
G
G
D017668:Age of Onset; D000368:Aged; D004247:DNA / Q000235:genetics / Q000276:immunology; D003924:Diabetes Mellitus, Type 2 / Q000453:epidemiology / Q000235:genetics*; D005190:Family; D005260:Female; D005602:France / Q000453:epidemiology; D005787:Gene Frequency; D018398:Homeodomain Proteins; D006801:Humans; D008297:Male; D008875:Middle Aged; D020125:Mutation, Missense / Q000235:genetics; D012150:Polymorphism, Restriction Fragment Length; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015534:Trans-Activators / Q000235:genetics*
D018398:Homeodomain Proteins; D015534:Trans-Activators; C084010:pancreatic and duodenal homeobox 1 protein; D004247:DNA