Genetic Variation In CHI3L1Gene Is Associated With Asthma In Childhood Of Fujian Minnan Area

OBJECTIVES：this study aim to investigate the association between CHI3L1geneSNPs and asthma in childhood from Fujian Minnan area and provide guide toprevention、diagnosis and treatment of asthma in childhood.METHODS:(1)We collected2ml peripheral blood from316patients diagnosed withasthma by Hospital(male164, female154, average age2.2±1.4) and297healthchildren(male152, female145, average age2.3±1.5) as control；(2)Genomic DNAwas extracted and performed MALTI-TOP mass spectrometry analysis to detect genetype and calculate frequency of SNP site rs4950928、rs10399805and rs883125inCHI3L1gene；(3) We used ELISA, chemiluminescence and flow cytometry analysisto examine YKL-40level, total IgE concentration and acidophil cells proportion,respectively, of all study subjects. Difference between asthma group and control orbetween genotypes was examined used above index;(4) SNPs frequency of asthmaand control group was analyzed. Hardy-Weinberg equation was used to examinecontrol group’s consistence to previous population data; SPSS13.0software was usedto analysis data; difference in SNPs frequency between asthma and control group wasanalyzed by χ2test; different genetic model combined with binary logistics regressionwas used to analyze data; OR value of different genotypes was calculated; two-tailedprobability test was used in all analysis and P＜0.05was considered as significance.RESULTS:(1)We found that total IgE and YKL-40concentration of asthma group is431.3±405.1IU/ml and59.3（34.2-89.5）ng/ml, respectively, which is significanthigher that in control group (IgE36.8±28.9IU/ml, YKL-4026.2（15.2-38.6）ng/ml, P＜0.001). However, proportion of acidophil cells was similar in both groups（P=0.747）.(2)MALDI-TOF mass spectrometry results indicated that distribution of gene type of rs10399805, TT、CT and CC, was similar in patient group and controlgroup（P=0.665）; Frequency of gene type GG in rs883125was significant higher inpatients group than control（P＜0.001）, however, with no significant difference intotal IgE and Ykl-40level, compared with other two gene types, GC and CC（P＞0.05）; Genetic variation in rs4950928was associated with risk of asthma. Frequencyof G allele was significantly increased in patients group（P＜0.001）. Patients with GGor CG in rs4950928were found to be detected with significant higher level of IgE andYkl-40, compared with patients with gene type CC（P＜0.05）.CONCLUSION:（1）YKL-40level in asthma group is significantly elevatedcompared to control group, indicating that YKL-40is potential biomarker for asthmadiagnosis.（2）Genetic variation in rs10399805and rs883125may associate withasthma occurrence and development, however, rs10399805is not an asthmasusceptibility gene in childhood of Minnan area.(3) G in rs883125may also associatewith higher risk of asthma, rs4950928-131C allele may provide protection againstasthma in childhood. Child with G allele in rs4950928is more incline to developasthma. G.