Search PubMed⌕ Search
Home/Archive/PubMed

PubMed · 2802524

Complement polymorphism in Greece.

C D Triantaphyllidis·A Ad'hiah·J Karkousis·S S Papiha
View original source ↗Export metadata ↓

Abstract

The polymorphisms of the complement components C2, C3, C4 and BF have been studied in a sample of 166 unrelated individuals from Northern Greece. The C3*F and BF*F allele frequencies of Greeks are within the range of frequencies reported from Europe. A single individual with a rare heterozygote variant C2C/C2A was found in Greeks. This C2*A allele was found for the first time in European Caucasoids. For the C4 system six different alleles were found at both C4A and C4B loci. There were a low frequency of the null alleles at the C4A locus and a relatively high incidence of gene duplications in this system.

Explore related subjects

Complement C2Complement C2aComplement C3Complement C4aComplement C4bComplement Factor DComplement System ProteinsGene FrequencyGreeceHumansMultigene FamilyPolymorphism, GeneticJournal Article

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

C D Triantaphyllidis, A Ad'hiah, J Karkousis, S S Papiha. Complement polymorphism in Greece.. https://doi.org/10.1080/03014468900000572

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed2003

Immunoglobulin deficiencies and susceptibility to infection among homozygotes and heterozygotes for C2 deficiency.

About 25% of C2-deficient homozygotes have increased susceptibility to severe bacterial infections. C2-deficient homozygotes had significantly lower serum levels of IgG2, IgG4, IgD, and Factor B, significantly higher levels of IgA and IgG3 and levels of IgG1 and IgM similar to controls. Type 1 (28 bp deletion in C2 exon 6 on the [HLA-B18, S042, DR2] haplotype or its fragments) and type II (non-type I) C2-deficient patients with increased susceptibility to bacterial infection had significantly lower mean levels of IgG4 (p < 0.04) and IgA (p < 0.01) than those without infections (who had a higher than normal mean IgA level) but similar mean levels of other immunoglobulins and Factor B. Of 13 C2-deficient homozygotes with infections, 85% had IgG4 deficiency, compared with 64% of 25 without infections. IgD deficiency was equally extraordinarily common among infection-prone (50%) and noninfection-prone (70%) homozygous type I C2-deficient patients. IgD deficiency was also common (35%) among 31 type I C2-deficient heterozygotes (with normal or type II haplotypes), but was not found in 5 type II C2-deficient heterozygotes or 1 homozygote. Thus, C2 deficiency itself is associated with many abnormalities in serum immunoglobulin levels, some of which, such as in IgG4 and IgA, may contribute to increased susceptibility to infection. In contrast, IgD deficiency appears not to contribute to increased infections and appears to be a dominant trait determined by a gene or genes on the extended major histocompatibility complex (MHC) haplotype [HLA-B 18, S042, DR2] (but probably not on type II C2-deficient haplotypes) similar to those previously identified on [HLA-B8, SC01, DR3] and [HLA-B18, F1C30, DR3].

Complement C2↗