Distribution of human kappa locus IGKV2-29 and IGKV2D-29 alleles in Swedish Caucasians and Hong Kong Chinese.
Polymorphism in the IGKV2-29 gene was shown to decrease the recombination frequency in B cells and to be important for immune responses to Haemophilus influenzae type b polysaccharide. By using the combination of PCR and restriction enzyme mapping, the distribution of IGKV2D-29 and IGKV2-29 gene alleles was estimated in two geographically and ethnically different groups. We found that V2D-29*01 homozygous individuals were most common in Swedish Caucasians (82%), but less common in the Chinese population of Hong Kong (28%). The homozygous V2D-29*02 genotype was found in 19% Chinese, but only in one Caucasian (1%). The frequency of the heterozygous V2D-29*01/V2D-29*02 genotype was also higher in the Chinese population (46%) compared with the Caucasians (7%). V2-29*01 homozygosity was more frequent among Caucasians (85%) than among Chinese (19%). In contrast, homozygous V2-29*02 individuals were over-represented in the Chinese population (18%), whereas only one was found among Caucasians (1%). Heterozygous V2-29*01/V2-29*02 individuals were also more common in the Chinese (63%) than the Caucasian (15%) population. Most Caucasians had the combination of V2D-29*01/V2D-29*01+V2-29*01/V2-29*01 (74%), while the most common genotype for Chinese was V2D-29*01/V2D-29*02+ V2-29*01/V2-29*02 (41%). Analysis of the association of V2D-29*02 and V2-29*02 alleles demonstrated a high degree of linkage, as for V2D-29*01 with V2-29*01. These data show a significant difference in the distribution of IGKV2D-29 and IGKV2-29 alleles among Swedish Caucasians and Hong Kong Chinese. This may help to explain differences in the occurrence of H. influenzae type b infection in the two populations. Evaluated methods for IGKV2D-29 and IGKV2-29 allele detection can be used for the screening allele polymorphisms in other particular patient groups.
Department of Clinical Immunology, University of Göteborg, Sweden. leonid.padyukov@immuno.gu.se
L
L
Padyukov
M
M
Hahn-Zoric
S R
SR
Blomqvist
M
M
Ulanova
S G
SG
Welch
A J
AJ
Feeney
Y L
YL
Lau
L A
LA
Hanson
D000483:Alleles; D044466:Asian People / Q000235:genetics*; D002681:China / Q000208:ethnology; D005787:Gene Frequency; D005803:Genes, Immunoglobulin / Q000235:genetics*; D006723:Hong Kong; D006801:Humans; D007135:Immunoglobulin Variable Region / Q000235:genetics*; D007136:Immunoglobulins / Q000235:genetics*; D013548:Sweden; D044465:White People / Q000235:genetics*
C014609:IgK; D007135:Immunoglobulin Variable Region; D007136:Immunoglobulins