Association between DEFB1 gene haplotype and herpes viruses seroprevalence in children with acute lymphoblastic...

Recent studies investigated the role of an unusual immune response to infective agents in the etiology of acute lymphoblastic leukemia (ALL) in children. Human beta-defensin-1 (hBD-1) is an anti-microbial peptide of the innate immune system, which exerts a killing role against pathogens. In the present study, three polymorphisms have been genotyped, namely, -52G/A, -44C/G and -20G/A, of DEFB1 gene, coding for hBD-1, in 40 ALL patients and 40 healthy children, and tested for an association between genetic variants of the protein and seroprevalence of antibodies for herpes viruses. The seroprevalence of cytomegalovirus (CMV), herpes simplex viruses (HSV) and Epstein-Barr virus (EBV) IgG antibodies in leukemic children was higher than that in controls (CMV: 61.5 vs. 27.3%, p = .008; HSV: 50 vs. 24.2%, p = .04; EBV: 61.3 vs. 46.2%, p = ns, respectively). Carriers of the GCA haplotype were found to have a significantly higher rate of immunization against CMV and HSV in ALL children compared to controls (CMV: 68 vs. 29%, p = .006; HSV: 56 vs. 26%, p = .04, respectively). No such observation was made when we analyzed the immunization against Epstein-Barr virus (EBV) by GCA haplotype in case and controls (58 vs. 40%, p = ns). These findings suggest that leukemic patients carrying untranslated variants of hBD-1 display a higher susceptibility to herpes viruses infections than controls.