External apical root resorption (EARR) is permanent shortening of the end of the tooth root. It is a common clinical complication of orthodontic treatment. Polymorphisms in the interleukin 1 (IL1) gene cluster have been related to an increased EARR risk. The aim of this study was to analyze possible associations ofIL1gene variants with EARR in Czech population.SUBJECTS AND METHODS:
In this case–control study, 32 patients with EARR (age 15.0 ± 4.1 years) and 74 controls (age 15.2 ± 5.3 years) were genotyped using PCR-based methods forIL1A(−889C/T),IL1B(+3953C/T), andIL1RN[IL1receptor antagonist, variable number tandem repeat (VNTR)] gene polymorphisms.RESULTS:
While no statistical significant differences in theIL1AandIL1Bgenotype, allele and reconstructedIL1haplotype frequencies between patients with EARR and controls were found, marginally significant differences were observed in the frequencies ofIL1RNvariant (P= 0.05 for *22 genotype andP= 0.06 for a short (2) allele). In addition, significant associations betweenIL1RN*12, *22 genotypes and the short (2) allele and EARR were identified in the subgroup of girls (P= 0.04 andP= 0.02,P= 0.02).CONCLUSIONS:
Although no significant role ofIL1A(−889C/T) andIL1B(+3953C/T) variants in EARR was confirmed,IL1RNVNTR may be associated with EARR, especially in girls.