Aims/hypothesis: The association between IL4R and type 1 diabetes has been tested in many studies in recent years, with contradictory results. The aim of this study was to re-evaluate the genetic association in type 1 diabetic nuclear families of mixed European background.
Subjects, materials and methods: We genotyped six non-synonymous single-nucleotide polymorphisms (SNPs) of the IL4R gene in 830 nuclear families as specified above, including a French Canadian subset.
Results: No association between type 1 diabetes and any SNP or haplotype was found by the transmission disequilibrium test.
Conclusions/interpretation: Previous positive reports may be due to population stratification as, according to HapMap data, allele frequencies in the IL4R region vary considerably by ethnicity.