[Study on the high-affinity IgE receptor beta gene polymorphism and its association with the susceptibility to allergic asthma in Han nationality of Hubei province].

ABSTRACT

OBJECTIVE: To determine whether 2 polymorphism sites of the high-affinity IgE receptor beta (Fc epsilon RI beta) gene were associated with allergic asthma in Han nationality of Hubei province in China. METHODS: DNA and clinical data were obtained from allergic asthma patients and were compared with those from a group of healthy control subjects. The subjects were genotyped for the -109C/T and a coding variant Glu237Gly in Fc epsilon RI beta gene by polymerase chain reaction-restriction fragment length polymorphism. RESULTS: (1) The genotype frequencies were 0.403 for -109T/T, 0.491 for -109T/C and 0.106 for -109C/C in allergic asthma patients in a Chinese population. No significant difference in the distribution of -109C/T polymorphism was found between allergic asthma patients and healthy control subjects; however, a homozygosity for the -109T allele was associated with increased total plasma IgE levels in patients with allergic asthma (F=7.523, P<0.01). (2) The frequency of Gly237Gly genotype was 0.051 in patient group, and 0.020 in control group. The allele frequencies of Gly237 in the patients and control were 0.236 and 0.136 respectively. There was a significant association between Gly/Gly genotype and allergic asthma. Among allergic asthma patients Gly237Gly was significantly associated with high IgE. CONCLUSION: These data suggested that the Gly237Gly genotype of the Fc epsilon RI beta gene conferred genetic susceptibility to allergic asthma in Chinese, which affected the total plasma IgE levels in the allergic asthma patients. And a homozygosity for the -109T allele was associated with increased total plasma IgE.