Abstract:

Objective The research aimed to investigate the relationship between DNA methylation ofm6A demethylase FTO gene and low/no response level of hepatitis B vaccine（HepB），and to provide scientific basisfor predicting individual response level of HepB and developing new HepB. Methods A total of 263 children aged8 to 9 months（who had completed hepatitis B immunization program）were recruited as subjects in a non⁃matchedcase ⁃control study from 2014 to 2016. According to the level of hepatitis B surface antibody（HBsAb），anti ⁃HBsconcentration < 100 mIU/mL was taken as the case group，and anti⁃HBs concentration ≥ 100 mIU/mL was taken asthe control group. DNA methylation level of FTO gene locus was detected by Methyl Target technique ，and therelationship between DNA methylation level of CpG island at 28 locus of FTO gene and immune response level ofHepB was analyzed. Results The DNA methylation level of FTO gene loci was low. The differences of DNA meth⁃ylation levels at FTO_1 gene locus 222 and FTO_2 gene locus 72 were statistically significant between the casegroup and control group. The level of DNA methylation at 222 locus of FTO_1 gene in case group was higher thanthat in control group（Z = -2.38，P = 0.009）. The level of DNA methylation at locus 72 of FTO_2 gene in casegroup was higher than that in control group（Z = -1.71，P = 0.044）. Conclusion It was suggested that methylationof FTO gene might occur in human body，and the low /non ⁃immune response level of HepB might be affected byFTO_1 gene locus 222 and FTO_2 gene locus 72.

Key words:

FTO, DNA methylation, hepatitis B vaccine, immune response level