OBJECTIVETo investigate frequency distribution of gene polymorphisms of PRF1 gene in children with hemophagocytic lymphohistiocytosis (HLH), and to explore whether the possible gene polymorphisms of PRF1 gene confer an increased risk of susceptibility to HLH.

METHODSForty-eight children who were diagnosed with HLH between January 2009 and December 2013 (HLH group) and 100 healthy children (control group) were enrolled in this study. The gene polymorphisms in the coding region of PRF1 gene, which consists of three exons and two introns, were genotyped by PCR, followed by direct sequencing.

RESULTSThree single nucleotide polymorphisms (SNPs) were revealed in the coding sequence of PRF1 in the 48 children with HLH. Seven SNPs were detected in the noncoding sequence. Other two SNPs in the noncoding sequence including rs10999426 and rs10999427 were detected only in 5 healthy children (5%). There was no significant difference in allelic frequencies of all the SNPs above between the HLH and control groups (P>0.05). Haplotype analysis showed there was a pair-wise linkage disequilibrium between rs10999426 and rs10999427 (D=1, r2=1), but there was no significant difference in the distribution of A-T haplotype between the HLH and control groups (P>0.05).

CONCLUSIONSThere is no association between gene polymorphisms of PRF1 gene and the susceptibility to HLH. There is a pair-wise linkage disequilibrium between rs10999426 and rs10999427, but a low detection rate of A-T haplotype in healthy children indicates that it might not play a protective role in the development of HLH.