Hypothesis: somatic hypermutation by gene conversion via the error prone DNA----RNA----DNA information loop.
A mechanism to explain somatic hypermutation in immunoglobulin variable region genes is proposed employing polynucleotide information transfer through the error prone DNA----RNA----DNA loop. During transcription of the rearranged V-region, the primary transcript undergoes either inappropriate termination, cleavage, or reverse transcriptase priming allowing a V-region specific reverse-transcriptase-integrase complex to synthesize a DNA copy of the rearranged V-region and integrate it, by homologous recombination, back into the normal chromosomal site. Some consequences and predictions of the hypothesis are discussed.
D000818:Animals; D001483:Base Sequence; D004247:DNA / Q000235:genetics; D004254:DNA Nucleotidyltransferases / Q000378:metabolism; D005785:Gene Conversion; D007135:Immunoglobulin Variable Region / Q000235:genetics*; D019426:Integrases; D008957:Models, Genetic; D009154:Mutation; D012313:RNA / Q000235:genetics; D012194:RNA-Directed DNA Polymerase / Q000378:metabolism; D014158:Transcription, Genetic
D007135:Immunoglobulin Variable Region; D012313:RNA; D004247:DNA; D004254:DNA Nucleotidyltransferases; D019426:Integrases; D012194:RNA-Directed DNA Polymerase