These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: DQA1*03 subtypes have different associations with DRB1 and DQB1 alleles.
    Author: Fernandez-Viña MA, Falco M, Gao X, Cerna M, Sun Y, Raimondi E, Stastny P.
    Journal: Hum Immunol; 1994 Apr; 39(4):290-8. PubMed ID: 8071103.
    Abstract:
    Polymorphisms outside the hypervariable regions of HLA class II alleles that do not affect the peptide-binding site are probably not under selective pressure and could therefore be useful as markers of the evolutionary pathways of the HLA class II haplotypes. We have analyzed such a polymorphism in the variants of DQA1*03, which differ at residue 160 encoded in exon 3. Our study included homozygous BCLs of the 10th IHWS and samples of a multiracial panel of 723 unrelated subjects which were also typed for allelic variations in exon 2 by hybridization with SSOP. BCLs having DQA1*03 and 131 selected DQA1*03-positive samples were typed for the dimorphism in exon 3 that distinguishes DQA1*0301 and DQA1*0302. DQA1*0301 was found to be exclusively associated with DQB1*0302, while samples carrying DQB1*0201, 0301, 0303, and 0401 always had DQA1*0302. A few haplotypes carrying DQB1*0302 had DQA1*0302. The fact that DQA1*0301 is completely included in DQB1*0302, and not vice versa, suggests that DQA1*0301 may have arisen from a mutation in a haplotype containing DQA1*0302-DQB1*0302. DQB1*0302 was found to be associated with all DR4 subtypes, suggesting possibly that the current variants of DRB1-DR4 may be of more recent origin. DRB1*0405 was the only subtype of DR4 which was not associated with DQA1*0301 and had multiple associations with the DQB1 alleles, therefore, perhaps representing the oldest allele of this group.
    [Abstract] [Full Text] [Related] [New Search]