ABSTRACT
Background: Growth hormone plays a significant role in determining craniofacial morphology. Mutations of its receptor gene might be associated with mandibular prognathism (MP). Purpose: The aim of the current study was to evaluate growth hormone receptor (GHR) gene polymorphisms in relation to facial dimensions. Material and Method: The study enrolled 65 participants with class III profile in MP group and 60 orthognathic control participants. Genomic DNA was extracted from a blood sample from the patients and the P561T and C422F polymorphisms of GHR gene were screened by PCR-RFLP method followed by Sanger sequencing of randomly selected samples to validate the genotyping results. Chi square was used to compare distribution of polymorphism in MP and control groups (p<0.05). Results: Heterozygous P561T mutation was found in 10.77% and 8.33% of MP and control groups, respectively (p=0.644) while none of the subjects had the C422F mutation. Sanger sequencing confirmed the genotyping results from the PCR-RFLP method. P561T polymorphism was significantly associated with ramus and lower facial height in MP patients and with ramus height in orthognathic patients (p<0.05). Conclusion: The results indicate that the P561T polymorphism of the GHR gene is associated with the vertical dimension of the mandible in an Iranian population.
Antecedentes: La hormona del crecimiento desempeña un papel importante en la determinación de la morfología craneofacial. Las mutaciones de su gen receptor podrían estar asociadas con el prognatismo mandibular (PM). Propósito: El objetivo del presente estudio fue evaluar dos polimorfismos del gen del receptor de la hormona del crecimiento (RHC) en relación con las dimensiones faciales. Materiales y Métodos: El estudio incluyó a 65 participantes con perfil de clase III en el grupo MP y 60 participantes de control ortognático. El ADN genómico se extrajo de una muestra de sangre de los pacientes y los polimorfismos P561T y C422F del gen RHC se seleccionaron mediante el método PCR-RFLP seguido de la secuenciación por Sanger de muestras seleccionadas al azar para validar los resultados del genotipo por RFLP. El test chi cuadrado se utilizó para comparar la distribución del polimorfismo en el grupo MP y grupo control (p<0.05). Resultados: Se encontró mutación heterocigota P561T en 10.77% y 8.33% de los grupos PM y control, respectivamente (p=0.644) mientras que ninguno de los sujetos tenía la mutación C422F. La secuenciación de Sanger confirmó los resultados de genotipado por el método PCR-RFLP. El polimorfismo P561T se asoció significativamente con la rama y la altura facial más baja en pacientes con PM y con la altura de la rama en pacientes ortognáticos (p<0.05). Conclusión: Los resultados indican que el polimorfismo P561T del gen RHC está asociado con la dimensión vertical de la mandíbula en una población iraní.
Subject(s)
Humans , Male , Female , Cephalometry/methods , Polymorphism, Single Nucleotide/genetics , Mandible/anatomy & histology , Prognathism , Growth Hormone , Chi-Square Distribution , Prevalence , Skull Base/anatomy & histology , Genotype , Iran/ethnology , Malocclusion , Malocclusion, Angle Class III/geneticsSubject(s)
Humans , Orthodontics, Corrective/methods , Malocclusion, Angle Class III/therapy , Phenotype , Prognathism/classification , Tooth Eruption/physiology , Tooth, Impacted/physiopathology , Cluster Analysis , Chromosome Mapping , Genetic Heterogeneity , Tooth Ankylosis/physiopathology , Imaging, Three-Dimensional/methods , Precision Medicine , Gene-Environment Interaction , Forecasting , Malocclusion, Angle Class III/classification , Malocclusion, Angle Class III/genetics , Maxilla/abnormalities , Maxillofacial Development/physiologySubject(s)
Humans , Ethnicity/genetics , Indians, South American/genetics , Malocclusion/genetics , Brazil/ethnology , Genotype , Haplotypes/genetics , Indians, South American/ethnology , Malocclusion, Angle Class III/ethnology , Malocclusion, Angle Class III/genetics , Malocclusion/ethnology , Tooth Wear/complicationsABSTRACT
This case report describes a 14 year old female patient, with pseudo-Class III incisor relationship on a mild Class III skeletal base with ankyloglossia. It highlights the relationship of an unfavorable soft tissue environment exerted by "tongue tie" and genetic factors proposed by the presence of family history in the development of a Class III malocclusion. Orthodontic treatment was provided on, a non-extraction basis to correct the Class III relationship. The patient was then referred for labial and lingual frenectomy using laser surgery to stabilize the achieved correction and facilitate the wear of orthodontic retainers by the patient. The first annual review carried out at the age of 17 years has revealed stable results