Single nucleotide polymorphisms in intron 2 of the human interleukin-1 receptor antagonist (IL-1Ra) gene: further definition of the IL-1 beta and IL-1Ra polymorphisms in North American Caucasians and Taiwanese Chinese.
Previous studies have suggested that a variable number tandem repeat (VNTR) polymorphism in the second intron of the interleukin-1 receptor antagonist (IL-1Ra) gene and the single nucleotide polymorphisms at positions -511 and +3954 of the IL-1beta gene might be associated with increased risks of chronic inflammatory diseases, autoimmune diseases and gastric cancer. In the present study, IL-1beta and IL-1Ra genotypes were analyzed among Asians in Taiwan and Caucasians in North America. We identified a novel polymorphism with 3 nucleotide substitutions in the IL-1Ra VNTR 2-repeat allele. One of the substitutions corresponds with the fourth 3' end nucleotide of the reverse primer that is often used for analysis of the IL-1Ra-associated VNTR locus. Mismatching between this primer and the 2-repeat allele can cause misleading amplification results when stringent conditions are used for annealing. The estimated haplotype frequencies of the variant IL-1 genes were significantly different between Taiwanese and Caucasians. The frequency of the pro-inflammatory IL-1Ra 2-repeat allele was significantly lower in Taiwanese than in Caucasians. In contrast, the frequencies of the pro-inflammatory IL-1beta -511T allele and +3954C allele were significantly higher among Taiwanese compared with Caucasians.
Tseng
L H
LH
Department of Medical Genetics, Pathology and Oncology, National Taiwan University Hospital, and Graduate Institutes of Clinical Medicine and Cancer Research Center, National Taiwan University, Taipei, Taiwan.
Chen
P J
PJ
Lin
M T
MT
Shau
W Y
WY
Chaung
S M
SM
Martin
P J
PJ
Hansen
J A
JA
D044466:Asian People / Q000235:genetics*; D020137:Base Pair Mismatch / Q000235:genetics; D017931:DNA Primers / Q000235:genetics; D005787:Gene Frequency / Q000276:immunology; D005838:Genotype; D006239:Haplotypes / Q000276:immunology; D006650:Histocompatibility Testing; D006801:Humans; D053590:Interleukin 1 Receptor Antagonist Protein; D007375:Interleukin-1 / Q000235:genetics*; D007438:Introns / Q000235:genetics* / Q000276:immunology; D018598:Minisatellite Repeats / Q000235:genetics; D009656:North America; D020641:Polymorphism, Single Nucleotide / Q000276:immunology; D017472:Receptors, Interleukin-1 / Q000037:antagonists & inhibitors*; D012795:Sialoglycoproteins / Q000235:genetics*; D013624:Taiwan; D044465:White People / Q000235:genetics*
D017931:DNA Primers; C507763:IL1RN protein, human; D053590:Interleukin 1 Receptor Antagonist Protein; D007375:Interleukin-1; D017472:Receptors, Interleukin-1; D012795:Sialoglycoproteins