Ethnic variation of Fcγ receptor polymorphism in Sami and Norwegian populations

Abstract

Summary Receptors for the Fc domain of IgG (FcγR) play a critical role in linking cellular and humoral immunity. The various FcγR genotypes may contribute to differences in infectious and immune‐related diseases in various ethnic populations. The Samis are the aboriginal inhabitants of Norway and Fennoscandinavia and differ ethnically from the Norwegians. The distribution of various immune‐related diseases has been reported to differ between Sami and Norwegians. This is the first study to evaluate the distribution of FcγR polymorphisms in a Sami population. Two hundred Samis were genotyped for polymorphisms in the FcγRIIA, FcγRIIIA and FcγRIIIB genes. The genotype and allele frequencies were compared with those of 272 healthy Norwegians. The Sami and Norwegian FcγRIIA, FcγRIIIA and FcγRIIIB genotypes differed significantly. The Samis had higher frequencies of the FcγRIIa‐H/H131, FcγRIIIa‐F/F158 and FcγRIIIb‐NA1/NA1 genotypes. The FcγR genotypes were non‐randomly distributed in both populations. These findings may be important for the prevalence of autoimmune and infectious diseases in the two populations.

Low frequency of the disease‐associated DRB1*15‐DQB1*06 haplotype may contribute to the low prevalence of multiple sclerosis in Sami

“…For instance, analysis of maternally inherited mitochondrial DNA and paternally inherited Y‐chromosomal variations suggests that the genetic separation of the Sami from other Europeans is best explained by assuming that the Sami are descendants of a narrow, distinctive subset of Europeans (20). Genetic differences between Sami and Caucasians are also shown in a previous study of HLA class I alleles (21), one study of HLA‐DRB1 and ‐DQB1 alleles in a small number of Russian Sami (21), as well as in our own studies of other selected polymorphisms (22, 23) and of class I and II alleles in a recently collected Norwegian Sami control cohort (Harbo et al, to be published).…”

“…To ensure the highest degree of Sami ancestry, all Sami controls had four grandparents who spoke Sami ( n = 200). These controls have previously been included in studies of polymorphisms in the IL‐10 and Fc‐γ receptor genes (22, 23). All Sami controls lived in Finnmark, their mean age was 64.9 years and 49% were female.…”

Norwegian Sami differs significantly from other Norwegians according to their HLA profile

“…Sami individuals were recruited at Karasjok Heart Center in Finnmark ( n = 200). These individuals have previously been included in studies on the polymorphisms of the IL‐10 and Fc‐ γ receptor genes and in a study of MS in the Sami population (5, 8, 9). For the present study, this sample set was typed with genomic methods for the HLA‐A , ‐ B , ‐ C , ‐DRB1 and ‐DQB1 loci.…”

SNP@Ethnos: a database of ethnically variant single-nucleotide polymorphisms

“…Some of the SNPs are found in disease-associated genes and cause functional protein defects. There are many reports on ethnic variations in genes associated with disease (23–27). Using SNP@Ethnos, the present study identified an interesting ESNP in a tyrosinase gene associated with albinism; this nonsynonymous ESNP may cause a functional defect, but this has yet to be shown.…”