MUTATION OF BCL-6 GENE IN NORMAL B-CELLS BY THE PROCESS OF SOMATIC HYPERMUTATION OF IG GENES

Immunoglobulin (Ig) genes are hypermutated in B lymphocytes that are t he precursors to memory B cells. The mutations are linked to transcrip tion initiation, but non-Ig promoters are permissible for the mutation process; thus, other genes expressed in mutating B cells may also be subject to somatic hypermutation. Significant mutations were not obser ved in c-MYC, S14, or alpha-fetoprotein (AFP) genes, but BCL-6 was hig hly mutated in a large proportion of memory B cells of normal individu als. The mutation pattern was similar to that of Ig genes.