Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1990-10-18
pubmed:databankReference
pubmed:abstractText
We have investigated the extent of DNA variability in intronic simple (gt)n(ga)m repeat sequences and correlated this to sequence polymorphisms in the flanking exon 2 of HLA-DRB genes. The polymerase chain reaction (PCR) was used to amplify a DNA fragment containing exon 2 and the repeat region of intron 2. The PCR products were separated on sequencing gels in order to demonstrate length hypervariability of the (gt)n(ga)m repeats. In a parallel experiment, the PCR products were cloned and sequenced (each exon 2 plus adjacent simple repeats) to characterize the simple repeats in relation to the HLA-DRB sequences. In a panel of 25 DRB1, DRB4, and DRB5 alleles new sequences were not detected. Restriction fragment length polymorphism (RFLP) subtyping of serologically defined haplotypes corresponds to translated DNA sequences in 85% of the cases, the exceptions involving unusual DR/DQ combinations. Many identical DRB1 alleles can be distinguished on the basis of their adjacent simple repeats. We found group-specific organization of the repeats: the DRw52 supergroup repeats differ from those of DRB1*0101, DRB4*0101, and DRB5*0101 alleles and from those of pseudogenes. Finally, we amplified baboon DNA and found a DRB allele with extensive similarity to DRB1 sequences of the DRw52 supergroup. The simple repeat of the baboon gene, however, resembles that of human pseudogenes. In addition to further subtyping, the parallel study of polymorphic protein and hypervariable DNA alleles may allow conclusions to be drawn on the relationships between the DRB genes and perhaps also on the theory of trans-species evolution.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0093-7711
pubmed:author
pubmed:issnType
Print
pubmed:volume
32
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
110-6
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Hypervariability of intronic simple (gt)n(ga)m repeats in HLA-DRB genes.
pubmed:affiliation
Institut für Medizinische Genetik (Charité), Berlin, German Democratic Republic.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't