Structure and multiplicity of genes for the human immunoglobulin heavy chain variable region.

Open Access
Publisher Website
Google Scholar
Abstract
Several genes for the variable region of immunoglobulin H chains (VH genes) were isolated from human fetal liver DNA by using a c[complementary]DNA plasmid probe containing a mouse VH sequence. The detectable VH genes are separated by 12-16 kbases of DNA, and hybridization experiments show .apprx. 23 hybridizing VH genes in DNA of 3 different individuals. The complete nucleotide sequence of one of these human VH genes shows that it belongs to the human VH III subgroup. The VH gene appears to contain an intervening sequence (104 bases in length) within a precursor sequence, between residues -4 and -5. The precursor sequence is itself 19 codons in length. The 3'' end of the V gene seems to be at codon 93 or 94, and this is followed by the conserved sequences C-A-C-A-G-T-G and G-A-C-A-C-A-A-A-C-C. The presence of these sequences suggests that similar enzymatic mechanisms are involved in the integration of V genes in both H and L chains.