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Mattila, P.S., Schugk, J., Wu, H. & Mäkelä, O., 1995 "Extensive allelic
sequence variation in the J region of the human immunoglobin heavy chain
gene locus", European Journal of Immunology, 25:2578-2582.
Abstract
During the initial stages of B lymphocyte differentiation heavy chain
variable (VH), diversity (DH) and joining (JH) gene segments recombine to
form a functional heavy chain variable region (VDJ) gene. Evidence for
genetic polymorphism of the human JH gene segments has been obtained from
mature rearranged VDJ sequences. We conducted an analysis of the published
rearrneged JH gene sequences and found that the JH alleles present in the
two published germ-line JH region sequences were rare (approx. 2%) in the
rearranged sequences. As an attempt to explain this discrepancy a 2.5kb
stretch of DNA containing all the six heavy chain JH region genes and the
most 3' DH gene segment, DHQ52, was amplified by the polymerase chain
reaction from 39 individuals and analyzed for restriction fragment length
polymorphism. Five new JH region haplotypes were found and sequenced. These
new haplotypes contained the coding segment allels that were frequent in
antibody genes. Surpisingly, a high number of interallelic differencies
(sic) in the non-coding sequence was found between the new and the two
previously published haplotypes implying that the haplotypes had been
separated early in evolution. In this respect the JH locus resembles HLA
loci.
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