Human Tcrb-V6.10 is a pseudogene with Alu repetitive sequences in the promoter region

Abstract

Tcrb-V6.10 represents an abnormal human V gene with an Alu insertion in the promoter, a point mutation of a conserved Cys at position 23, and a missing nonamer within the usually conserved recombinase signal sequence. Here it is shown that b-V6.10 is found in the genome of most individuals, is normally located in the Tcrb-V locus on chromosome 7, but is not rearranged or transcribed. Thus, it is likely that the abnormal signal sequence precludes recombination and that the Alu insertion results in a disabled promoter, indicating the functional importance of the affected regions. Tcrb-V6.10 probably evolved by duplication of an ancestral Tcrb V13-V6-V5 cassette, like other members of the large b-V6 subfamily, and more recently became inactivated into a pseudogene.