Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1988-5-10
pubmed:abstractText
Statistical analyses of DNA sequences of globin genes (beta A, beta C, and gamma) from goat and sheep (including new sequence information for the second intron of sheep beta A and gamma, kindly provided by A. Davis and A. W. Nienhuis) indicate that the rates of nonsynonymous substitution in these genes have been greatly accelerated following the gene duplication separating gamma and the ancestor of beta A and beta C and the gene duplication separating beta A and beta C. In both cases the acceleration was apparently due to relaxation of purifying selection (functional constraints) rather than advantageous mutations because acceleration occurred only in less important parts of the beta globin chain. The rates of nonsynonymous substitution in these genes are estimated to be about 2.3 x 10(-9) per site per year, which is three times higher than that for the divergence between human beta and mouse beta major globin genes. Our analyses further suggest that the rate of synonymous substitution in functional genes and the rate of substitution in pseudogenes are approximately equal and are between 2.8 x 10(-9) and 5.0 x 10(-9) and that the rate of substitution in introns is about 3.0 x 10(-9). The divergence time between beta A and beta C and that between gamma and the beta A-beta C pair are about 12 and 30 million years, respectively. The proportion of transition mutations is estimated to be 64%, two times higher than expected under random mutation but considerably lower than the 96% estimated for animal mitochondrial DNA.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0737-4038
pubmed:author
pubmed:issnType
Print
pubmed:volume
1
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
94-108
pubmed:dateRevised
2010-11-18
pubmed:meshHeading
pubmed:year
1983
pubmed:articleTitle
Rapid evolution of goat and sheep globin genes following gene duplication.
pubmed:affiliation
Center for Demographic and Population Genetics, University of Texas, Houston 77025.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.