Relationship between P561T and C422F polymorphisms in growth hormone receptor gene and mandibular prognathism

Abstract

Objective: To evaluate the allele and genotype frequencies of the P561T and C422F polymorphic sites of the growth hormone receptor (GHR) gene and the relationship between mandibular prognathism (MP) and these two single-nucleotide polymorphisms (SNPs). Materials and Methods: A total of 99 subjects with severe skeletal Class III MP who planned to undergo orthognathic surgery and 99 subjects with Class I occlusion were examined in this study to evaluate the relationship between MP and two SNPs in exon 10 of the GHR gene. GHR was chosen as a candidate gene because growth hormone plays an important role in cartilage growth. A blood sample was used to extract genomic DNA, and the polymerase chain reaction-restriction fragment length polymorphism method was used to determine genotypes of P561T and C422F. The Minitab 14.0 packet program was used to perform statistical analysis. Results: Allele frequencies of the C422F and P561T variants were determined. Because of the low allele frequency of the control group, statistical analysis could not be performed to test the difference between MP and control groups. Therefore, the data were combined to determine the association between the P561T polymorphism and craniofacial measurements. Effective mandibular length (condylion-gnathion) and lower face height (anterior nasal spina-menton) were associated with the P561T variant. Conclusion: This finding supports that the GHR might be a candidate gene for mandibular morphogenesis in this population. (Angle Orthod. 2014;84:803-809.)

Growth hormone receptor gene variant and three-dimensional mandibular morphology

“…In previous reports concerning the relationship between GHR gene variants and mandibular morphology, analysis by twodimensional lateral cephalograms [13][14][15][16][17][18] revealed relationships between mandibular ramus length and variants rs6184 and rs6182. 13,16 However, owing to the complex structure of the mandible, two-dimensional evaluation using cephalograms cannot be used for precise measurement of the mandible.…”

“…19 In the present study, we examined the association between the actual length of the mandibular bone and GHR gene variants using three-dimensional analysis. In previous reports, GHR gene SNPs (rs6180, rs6182, and rs6184) were described to be related to mandibular morphology, [13][14][15][16][17][18] with SNPs rs6182 and rs6184 in complete linkage disequilibrium. In this study, we examined two SNPs (rs6180 and rs6184).…”

“…The relationship between rs6184 in exon 10 of GHR and mandibular ramus height in a Japanese population, as well as similar findings in Korean and Turkish populations, have been previously reported. [13][14][15] Mandibular ramus length was significantly shorter in a Japanese population with genotype CC of variants rs6184 or genotype GG of rs6182. 16 Furthermore, a relationship between the rs6180 variant and mandibular ramus length has been reported in a Chinese population.…”

“…17 In young Japanese children, the rs6184 variant of the GHR gene has an inhibitory effect on mandibular growth. 18 Previous studies examining the relationship between craniofacial morphology and GHR [13][14][15][16][17][18] have used lateral cephalograms to measure craniofacial morphology. However, there are limitations associated with the application of two-dimensional data from lateral cephalograms to the evaluation of craniofacial morphology, which has a complex structure.…”

Association of Growth Hormone Receptor Gene Variants with Mandibular Form in an Egyptian Population

“…Allele and genotype frequencies of the GHR rs6182 and rs6184 variants and their relationship to mandibular prognathism were examined in a Turkish cohort consisting of 101 patients with Class mandibular prognathism and 99 individuals with normal occlusion. The rs6184 variant was associated with effective mandibular length condylion-gnathion and lower face height anterior nasal spine-menton 15 .…”