Studies of the variability of the genes encoding the insulin-like growth factor I receptor and its ligand in relation to type 2 diabetes mellitus

Research output: Contribution to journalJournal articleResearchpeer-review

Søren K. Rasmussen, Corinne Lautier, Lars Hansen, Søren M. Echwald, Torben Hansen, Claus T. Ekstrøm, Søren A. Urhammer, Knut Borch-Johnsen, Florin Grigorescu, Robert J. Smith, Oluf Pedersen

Insulin-like growth factor I (IGF-I) is an important regulator of many aspects of growth, differentiation, and development, and as low birth weight has been associated with impaired glucose tolerance and overt type 2 diabetes in adult life, we considered the genes encoding the IGF-I and the IGF-I receptor (IGF-IR) as candidates for low birth weight, insulin resistance, and type 2 diabetes. Here we report the mutational analysis of the coding regions of the IGF-I and IGF-IR performed on genomic DNA from probands of 82 Danish type 2 diabetic families. No mutations predicting changes in the amino acid sequences of the IGF-I or IGF-IR genes were detected, but several silent and intronic polymorphisms were found. The impact of the most prevalent polymorphism, GAG1013GAA of the IGF-IR, was evaluated in a population-based sample of 349 young healthy subjects, where the variant had an allele frequency of 0.44 (95% confidence interval, 0.40-0.48). No significant relationships between this variant and birth weight, birth length, or insulin sensitivity index were detected. In addition, we did not observe any significant differences in allelic frequencies of the codon 1013 variant between 395 type 2 diabetic patients (allele frequency, 0.52; 95% confidence interval, 0.49-0.55) and 238 matched glucose-tolerant control subjects (allelic frequency, 0.47; 95% confidence interval, 0.43-0.50). In conclusion, variability in the coding regions of IGF-I and the IGF-IR does not associate with reduced birth weight, insulin sensitivity index, or type 2 diabetes in the Danish population.

Original languageEnglish
JournalJournal of Clinical Endocrinology and Metabolism
Volume85
Issue number4
Pages (from-to)1606-1610
Number of pages5
ISSN0021-972X
DOIs
Publication statusPublished - 1 Dec 2000

ID: 203910183