In the genome of a germ-line cell, the genetic information for an immunoglobulin polypeptide
chain is contained in multiple gene segments scattered along a chromosome. During
the development of bone marrow-derived lymphocytes, these gene segments are assembled
by recombination which leads to the formation of a complete gene. In addition, mutations
are somatically introduced at a high rate into the amino-terminal region. Both somatic
recombination and mutation contribute greatly to an increase in the diversity of antibody
synthesized by a single organism.