title: Two V(H)5 family genes expressed by human peripheral B cells display differential mutational frequencies in the V(H) region.
abstract: The heavy chain variable segment gene (V(H))5 family, one of the seven immunoglobulin (Ig) V(H) families, contains two functional genes, VH251 and VH32. To investigate functional differences between these V(H)5 family genes, V(H) segments expressed by human peripheral B cells were sequenced and analyzed. One hundred fifty-three sequences with unique V(H)DJ(H) recombinations were obtained from 17 adults. The mutational frequency of VH32 derived sequences (6.4%) was higher than that of VH251 derived sequences (4.4%), resulting in a significant difference (P<0.01). Significant differences in mutational frequencies between VH251 and VH32 derived sequences were observed in CDRs and FRs. No significant differences were found in CDR3 length distribution, D segment usage, or J(H) segment usage between VH251 and VH32 derived sequences. These results suggest that mutational frequency is affected, in part, by V(H) gene structure. The difference may occur after recombinational events in B cell development.
authors.affiliation: Department of Environmental Medicine and Infectious Diseases, Faculty of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Yong
authors.initials: Y
authors.lastname: Chong
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Ikematsu
authors.forename: Masayuki
authors.initials: M
authors.lastname: Murata
authors.forename: Kouzaburo
authors.initials: K
authors.lastname: Yamaji
authors.forename: Shigeki
authors.initials: S
authors.lastname: Nabeshima
authors.forename: Seizaburo
authors.initials: S
authors.lastname: Kashiwagi
authors.forename: Jun
authors.initials: J
authors.lastname: Hayashi
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000595:Amino Acid Sequence; D001402:B-Lymphocytes / Q000378:metabolism*; D001483:Base Sequence; D003062:Codon; D022801:Complementarity Determining Regions / Q000737:chemistry / Q000235:genetics; D005260:Female; D006801:Humans; D007143:Immunoglobulin Heavy Chains / Q000737:chemistry / Q000235:genetics*; D007135:Immunoglobulin Variable Region / Q000737:chemistry / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D009154:Mutation
chemical_list: D003062:Codon; D022801:Complementarity Determining Regions; D007143:Immunoglobulin Heavy Chains; D007135:Immunoglobulin Variable Region