Potential interactions among single nucleotide polymorphisms in bone‐ and cartilage‐related genes in skeletal malocclusions

Objective To investigate SNPs in bone‐ and cartilage‐related genes and their interaction in the aetiology of sagittal and vertical skeletal malocclusions. Settings and sample population This study included 143 patients and classified as follows: skeletal class I (n = 77), class II (n = 47) and class III (n = 19); maxillary retrusion (n = 39), protrusion (n = 52) and well‐positioned maxilla (n = 52); mandibular retrognathism (n = 50), prognathism (n = 50) and well‐positioned mandible (n = 43); normofacial (n = 72), dolichofacial (n = 55) and brachyfacial (n = 16). Materials and methods Steiner's ANB, SNA, SNB angles and Ricketts’ NBa‐PtGn angle were measured to determine the skeletal malocclusion and the vertical pattern. Nine SNPs in BMP2, BMP4, SMAD6, RUNX2, WNT3A and WNT11 were genotyped. Chi‐squared test was used to compare genotypes among the groups. Multifactor dimensionality reduction (MDR) and binary logistic regression analysis, both using gender and age as co‐variables, were also used. We performed Bonferroni correction for multiple testing. Results Significant associations at P