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

J Mol Biol. 1997 Jul 25;270(4):587-97. doi: 10.1006/jmbi.1997.1141.


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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Base Sequence
  • Chromosome Mapping
  • Chromosomes, Human, Pair 14*
  • Evolution, Molecular
  • Germ Cells
  • Humans
  • Immunoglobulin D / genetics*
  • Immunoglobulin Joining Region / genetics
  • Immunoglobulin Variable Region / genetics
  • Molecular Sequence Data
  • Open Reading Frames
  • Recombination, Genetic*


  • Immunoglobulin D
  • Immunoglobulin Joining Region
  • Immunoglobulin Variable Region