Growth hormone receptor gene is related to root length and tooth length in human teeth

Abstract

Objectives: To examine the relationship between tooth length and growth hormone receptor (GHR) gene variants in a healthy Japanese population. Materials and Methods: The subjects consisted of 193 Japanese adults (69 men, 124 women), aged 13 to 56 years. Genomic DNA was extracted from saliva and genotyped GHR rs6184 and rs6180 variants using the Taqman genotyping. Computed tomography (CT) images were acquired using a dental cone-beam CT scanner and reconstructed using open-source OsiriX medical image processing software. The maxillary (upper; U) and mandibular (lower, L) central incisors (1), lateral incisors (2), canines (3), first premolars (4), second premolars (5), first molars (6), and second premolars (7) were evaluated. Teeth were assessed for crown height (CH), root length (RL), overall tooth length (CþR), and crown to root ratio (C/R). The relationships between GHR variants and CH, RL, CþR, and C/R were statistically examined. Results: The GHR variant rs6184 was associated with the root lengths and tooth length for the upper and lower lateral incisors and upper canines (U2 RL; U3 RL, CþR; L2 RL [P, .05]). Conclusions: The results indicate that the GHR rs6184 variant is associated with tooth length and ratio dimensions in a Japanese cohort. Further studies utilizing a larger sample size are needed to confirm this finding.