Association of genetic polymorphism of interleukin 1-alpha and interleukin 1-beta with external apical root resorption in orthodontic patients

To assess the allele rs 1143634 in IL-1β and rs1800587 in IL-1α in patients for orthodontically induced external apical root resorption (EARR). Intra-oral periapical radiograph (IOPA) of maxillary incisors of 142 Patients were evaluated for resorption at two time points; before the start of fixed mechanotherapy (T1) and after one year of treatment (T2). The individuals with root resorption < 2 mm were categorized as a control group (group 1; n = 90), and resorption > 2 mm were categorized as case group (group 2; n = 52). Buccal swabs of all patients were taken and DNA could be isolated in 95 out of 142 samples (group 1 {n = 58}, group 2 {n = 37}), which were then screened for the selected two polymorphic targets to determine the nucleotide status of these targets. Tetra-primer ARMS PCR reactions were carried out using all 4 primers for each polymorphism. rs11800587 was not associated with risk of EARR in any inheritance model. Chi-square test for association of alleles with EARR revealed that rs1143634 was associated with the risk of EARR in an allelic model in such a way that A allele of this SNP increased the risk of EARR 4 folds [OR = 4.375; P = 0.016]. However, the adjusted level of significance using the Holm-Bonferroni method for rs1143634 was P < 0.010 for A and G comparison rendering the results non-significant. SNP rs1143634 and SNP rs11800587 were not associated with risk of EARR in any inheritance model.