Human leukocyte antigen class II alleles and dental caries in a child population

PURPOSE: The purpose of this study was to investigate a possible relationship between human leukocyte antigens (HLAs) DRB1 and DQB1, dental caries, and colonization by mutans streptococci (MS) in children. METHODS: Sixty children were clinically examined for caries in accordance with World Health Organization criteria and methods. Thereafter, subjects were assigned into 2 groups: (1) high-caries children (dft and DMFT > or = 5); and (2) caries-free children (dft and DMFT = 0). Fresh saliva samples were collected and testedfor mutans streptococci, after which the subjects were placed into 2 groups, having either high (> or =10(5) colony-forming units [CFU]/mL saliva) or low (< 10(5) CFU/mL saliva) numbers of micro-organisms in saliva. The polymerase chain reaction/sequence specific primer method was used to determine HLA DNA typing from fresh blood samples. RESULTS: There was no significant difference between the frequency of HLA alleles in high-caries and caries-free subjects. Although chi-square test suggested an association for HLA-DRB1*01 and HLA-DQB1*03 with the salivary numbers of MS (P = .026 and P = .009, respectively), these could not be confirmed by logistic regression analysis (P = .188 and P = .101, respectively). CONCLUSIONS: The results obtained fail to establish an association between human leukocyte antigen alleles DRB1 and DQB1 and salivary numbers of MS in the selected child population.