OBJECTIVETo investigate the link between the polymorphism of -109 and Glu237 in the high-affinity IgE receptor beta (FcepsilonRIbeta) gene and susceptibility to allergic asthma in a Chinese population.

METHODBlood samples from 216 allergic asthma patients and 198 age- and sex-matched controls were studied. A -109C/T and a coding variant Glu237Gly in FcepsilonRIbeta were detected with polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).

RESULTSThe genotype frequencies were 0.403 for -109T/T, 0.491 for -109T/C and 0.106 for -109C/C in allergic asthma in a Chinese population. No significant difference in the distribution of -109C/T polymorphism was found between allergic asthma subjects and healthy controls, however, homozygosity for the -109T allele was associated with increased total plasma IgE levels in subjects with allergic asthma (F = 4.020, P < 0.05). The allele frequency of Gly237 in the patients and control was 0.236 and 0.136 respectively. There was a significant association between the Gly/Gly genotype and allergic asthma. Among allergic asthma patients Gly237 was significantly associated with high IgE levels.

CONCLUSIONSThese results suggest that the Gly237 variant of the FcepsilonRIbeta gene is involved in the development of allergic asthma. The -109C/T and Glu237Gly polymorphisms are two of the genetic factor identified thus far, which affect total plasma IgE levels of allergic asthma patients in a Chinese population.