Single-nucleotide polymorphisms of HLA and Polygonum multiflorum-induced liver injury in the Han Chinese population

BACKGROUND Polygonum multiflorum is one of the leading causes of herb-induced liver injury in China.HLA-B*35:01 is reported to be a potential biomarker of Polygonum multiflorum-induced liver injury(PM-DILI).However,little is known about the relationship between single-nucleotide polymorphisms(SNPs) and PM-DILI.AIM To identify SNPs that indicate susceptibility to PM-DILI METHODS We conducted a systematic study enrolling 382 participants from four independent hospitals,including 73 PM-DILI patients,118 patients with other drug-induced liver injury(other-DILI) and 191 healthy controls.Whole-exome sequencing was performed for 8 PM-DILI patients and 8 healthy controls who were randomly selected from the above subjects.Nineteen SNPs that showed high frequencies in the 8 PM-DILI patients were selected as candidate SNPs and then screened in 65 PM-DILI patients,118 other-DILI patients and 183 healthy controls using the MassARRAY system.HLA-B high-resolution genotyping was performed for the 73 PM-DILI and 118 other-DILI patients.The Han-MHC database was selected as a population control for HLA-B analysis.P <6.25 x 103 after Bolferroni correction was considered significant.RESULTS The frequencies of rslll686806 in the HLA-A gene,rs1055348 in the HLA-B gene,and rs202047044 in the HLA-DRB1 gene were significantly higher in the PM-DILI group than in the control group [27.2% vs 11.6%,P=1.72×105,odds ratio(OR)=3.96,95% confidence interval(Cl):2.21-7.14;42.5% vs 8.6%,P=1.72×10-19 OR=13.62,95% CI:7.16-25.9;22.9% vs 8.1%,P=4.64×106,OR=4.1,95% CI:2.25-7.47].Only rs1055348 showed a significantly higher frequency in the PM-DILI group than in the other-DILI group(42.5% vs 13.6%,P=1.84×10-10,OR=10.06,95% Cl:5.06-20.0),which suggested that it is a specific risk factor for PM-DILI.rs1055348 may become a tag for HLA-B*35:01 with 100% sensitivity and 97.7% specificity in the PM-DILI group and 100% sensitivity and 98.1% specificity in the other-DILI group.Furthermore,HLA-B*35:01 was confirmed to be associated with PM-DILI with a frequency of 41.1% in the PM-DILI group compared with 11.9%(P=4.30×10-11,OR=11.11,95% CI:5.57-22.19) in the other-DILI group and 2.7%(P=6.22×10-166,OR=62.62,95% Cl:35.91-109.20) in the Han-MHC database.CONCLUSION rslll686806,rs1055348,and rs202047044 are associated with PM-DILI,of which,rs1055348 is specific to PM-DILI.As a tag for HLA-B*35:01,rs1055348 may become an alternative predictive biomarker of PM-DILI.