Interleukin-1B (IL-1B-31 and IL-1B-511) and interleukin-1 receptor antagonist (IL-1Ra) gene polymorphisms in primary immune thrombocytopenia.

BACKGROUND: Immune thrombocytopenia (ITP) is an immune-mediated disease caused by autoantibodies against platelets membrane glycoproteins GPIIb/IIIa and GPIb/IX. The etiology of ITP remains unclear. This study evaluated the association of polymorphisms in interleukin (IL)-1B-31, IL-1B-511, and IL-1Ra with ITP. METHODS: Genotyping of IL-1B-31, IL-1B-511, and IL-1Ra was performed in 118 ITP patients and 100 controls by polymerase chain reaction restriction fragment length polymorphism and detection of variable number tandem repeats. RESULTS: Genotype differences in IL-1B-31 and IL-1Ra were significantly associated with ITP. Patients showed a higher frequency of the IL-1B-31 variant allele (T) and a 1.52-fold greater risk of susceptibility to ITP (odds ratio [OR]=1.52, 95% confidence interval [CI]=1.04-2.22, P=0.034). The frequencies of both homozygous and heterozygous variant genotypes of IL-1B-31 were higher (OR=2.33, 95% CI=1.069-5.09, P=0.033 and OR=2.044, 95% CI=1.068-39, P=0.034) among patients and were significantly associated with ITP susceptibility. Both homozygous and heterozygous variant genotypes of IL-1Ra were also more frequent (OR=4.48, 95% CI=1.17-17.05, P=0.0230 and OR=1.80, 95% CI=1.03-3.14, P=0.0494) among patients and were associated with ITP risk. IL-1B-31 and IL-1Ra also showed significant association with severe ITP. However, IL-1B-511 was not associated with ITP. CONCLUSION: IL-1B-31 and IL-1Ra polymorphisms may significantly impact ITP risk, and they could be associated with disease severity, which may contribute to the pathogenesis of ITP.

Interleukin-1B (IL-1B-31 and IL-1B-511) and interleukin-1 receptor antagonist (IL-1Ra) gene polymorphisms in primary immune thrombocytopenia

BACKGROUND: Immune thrombocytopenia (ITP) is an immune-mediated disease caused by autoantibodies against platelets membrane glycoproteins GPIIb/IIIa and GPIb/IX. The etiology of ITP remains unclear. This study evaluated the association of polymorphisms in interleukin (IL)-1B-31, IL-1B-511, and IL-1Ra with ITP. METHODS: Genotyping of IL-1B-31, IL-1B-511, and IL-1Ra was performed in 118 ITP patients and 100 controls by polymerase chain reaction restriction fragment length polymorphism and detection of variable number tandem repeats. RESULTS: Genotype differences in IL-1B-31 and IL-1Ra were significantly associated with ITP. Patients showed a higher frequency of the IL-1B-31 variant allele (T) and a 1.52-fold greater risk of susceptibility to ITP (odds ratio [OR]=1.52, 95% confidence interval [CI]=1.04–2.22, P=0.034). The frequencies of both homozygous and heterozygous variant genotypes of IL-1B-31 were higher (OR=2.33, 95% CI=1.069–5.09, P=0.033 and OR=2.044, 95% CI=1.068–39, P=0.034) among patients and were significantly associated with ITP susceptibility. Both homozygous and heterozygous variant genotypes of IL-1Ra were also more frequent (OR=4.48, 95% CI=1.17–17.05, P=0.0230 and OR=1.80, 95% CI=1.03–3.14, P=0.0494) among patients and were associated with ITP risk. IL-1B-31 and IL-1Ra also showed significant association with severe ITP. However, IL-1B-511 was not associated with ITP. CONCLUSION: IL-1B-31 and IL-1Ra polymorphisms may significantly impact ITP risk, and they could be associated with disease severity, which may contribute to the pathogenesis of ITP.

Interleukin-1 receptor antagonist gene polymorphism and obesity: A pilot study from north India.

The main adverse consequences of excess bodyweight are cardiovascular disease, type II diabetes, and several cancers, IL-1Ra serum concentration has been reported earlier to increase in human obesity and it is therefore assumed that the polymorphism of IL-1Ra may influence cytokine production. We designed this study to investigate whether the IL-1Ra polymorphism was associated with obesity. A total number of 103 individuals; 19 lean (BMI<25 Kg/m(2)), 51 overweight (BMI 25-29.9 Kg/m(2)) and 33 obese (BMI≥30.0 Kg/m(2)) were enrolled in this study. Genotyping was performed using a polymerase chain reaction PCR amplification of the intron-2 fragment harboring a variable number of tandem repeat (VNTR) nucleotide sequences 86 pb of tandem repeat. The PCR products were separated on 2% agarose gel. Statistical analysis was performed using SPSS software (version 11.5). We found no significant difference in genotype and allele frequencies between the three groups; lean vs. overweight and lean vs. obese (p=0.323; 0.202; 0.123 and 0.068 resp). However, an increased risk for obesity had a propensity to be higher in those having genotype II/II. This genotype has been reported to be a 'high producer' of IL-1Ra. Although no statistically significant relationship between IL-1Ra polymorphism and BMI was observed, however, a trend towards an increase of allele(*)II in overweight and obese group was observed. This may suggest that IL-1Ra appears to be induced by inflammatory stimuli as well as obesity-associated factors. This is relatively a pilot study: but nevertheless, may assist in identifying the pathophysiological cause for obesity.

Study of interleukin-1 receptor antagonist (IL-1Ra) gene polymorphism in healthy individuals from Northern India.

Cytokines play a key role in immune responses and inflammation. IL-1Ra is a naturally occurring structural variant of IL-1 that competitively inhibits receptor binding of IL-1. We have investigated the polymorphism in intron-2 of the interleukin-1 receptor antagonist gene in North Indian population. This genetic variation has been of great interest due to its possible association with a variety of human diseases primarily of epithelial and endothelial cell origin such as urolithiasis etc. Allele frequencies of the IL-1Ra polymorphism vary among different populations but there is no data till date reported from India. The present study was carried out to determine the IL-1Ra gene Polymorphism in 165 normal unrelated individuals from North India. We obtained an allelic frequency of 63.94, 30.61, 4.55, 0.90 for A, B, C and D allele and percentage of genotypes AA, BB, CC, DD, A/B, A/C, A/D and B/C were 49.7, 18.2, 2.42, 0.60, 24.2, 3.63, 0.60, 0.60 respectively. Our results suggested that the frequency and distribution of this polymorphism in India is substantially different from other populations and ethnic groups.