Two V(H)5 family genes expressed by human peripheral B cells display differential mutational frequencies in the V(H) region.
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.
Chong
Yong
Y
Department of Environmental Medicine and Infectious Diseases, Faculty of Medical Sciences, Kyushu University, Fukuoka, Japan.
Ikematsu
Hideyuki
H
Murata
Masayuki
M
Yamaji
Kouzaburo
K
Nabeshima
Shigeki
S
Kashiwagi
Seizaburo
S
Hayashi
Jun
J
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
D003062:Codon; D022801:Complementarity Determining Regions; D007143:Immunoglobulin Heavy Chains; D007135:Immunoglobulin Variable Region