Sequence of the human immunoglobulin diversity (D) segment locus: a systematic analysis provides no evidence for the use of DIR segments, inverted D segments, "minor" D segments or D-D recombination.
We have determined the complete nucleotide sequence of the human immunoglobulin D segment locus on chromosome 14q32.3 and identified a total of 27 D segments, of which nine are new. Comparison with a database of rearranged heavy chain sequences indicates that the human antibody repertoire is created by VDJ recombination involving 25 of these 27 D segments, extensive processing at the V-D and D-J junctions and use of multiple reading frames. We could find no evidence for the proposed use of DIR segments, inverted D segments, "minor" D segments or D-D recombination. Conventional VDJ recombination, which obeys the 12/23 rule, is therefore sufficient to explain the wealth of lengths and sequences for the third hypervariable loop of human heavy chains.
Corbett
S J
SJ
MRC Centre For Protein Engineering, Hills Road, Cambridge, CB2 2QH, U.K.
Tomlinson
I M
IM
Sonnhammer
E L
EL
Buck
D
D
Winter
G
G
D001483:Base Sequence; D002874:Chromosome Mapping; D002883:Chromosomes, Human, Pair 14; D019143:Evolution, Molecular; D005854:Germ Cells; D006801:Humans; D007072:Immunoglobulin D / Q000235:genetics*; D007133:Immunoglobulin Joining Region / Q000235:genetics; D007135:Immunoglobulin Variable Region / Q000235:genetics; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D011995:Recombination, Genetic
D007072:Immunoglobulin D; D007133:Immunoglobulin Joining Region; D007135:Immunoglobulin Variable Region