Mutations in Exons 1 and 2 of PAX9 Gene and Hypodontia
Poster Number
16
Introduction/Abstract
Hypodontia is one of the most common dental anomalies that result in aesthetic and functional problems. A wide range of prevalence values for missing teeth has been reported ranging from 1.6% to 25.4% in adult population. Our understanding of the genetic basis of tooth agenesis is still limited. Several genes have been explored, including, but not limited to PAX9 and MSX1. The normal function of the PAX9 gene, a transcription factor that plays an important role in signaling between epithelial and mesenchymal cells during tooth development, seems to be critical during development of dental lamina.
Purpose
The goal of our study was to identify genetic mutations in exon 1 and exon 2 of PAX9 gene, commonly associated with a lack of tooth development in probands and their close relatives.
Method
Our sample consisted of 66 individuals with congenitally missing teeth and 50 of their relatives. Saliva specimens were collected from all individuals. Most of saliva specimens were collected using our own protocol. Modified chelex method was used to extract DNA. A smaller number of specimens were collected using Oragene saliva kit. Following DNA isolation, PCR was done using specific primers for each single nucleotide polymorphism, agarose electrophoresis followed to confirm PCR product, which was then purified and sent to sequencing laboratory. The sequenced specimens were analyzed for PAX9 genotypes.
Results
Out of 66 individuals with missing teeth and 50 their family members that were genotyped, 13 mutations (9 in probands and 4 in family members) in exons one or two of PAX9 gene were found. Among 76 controls, none had a mutation in exons one or two of PAX9 gene.
Significance
Results of this pilot study suggest a rather strong association of exon 1 and exon 2 mutations of PAX9 gene in individuals with hypodontia in our sample. Evaluation of a larger sample will enable us to draw more definitive conclusions. Our study continues and, in addition to PAX9, also MSX1and BMP4 gene polymorphisms are studied.
Location
DeRosa University Center, Stockton campus, University of the Pacific
Format
Poster Presentation
Mutations in Exons 1 and 2 of PAX9 Gene and Hypodontia
DeRosa University Center, Stockton campus, University of the Pacific
Hypodontia is one of the most common dental anomalies that result in aesthetic and functional problems. A wide range of prevalence values for missing teeth has been reported ranging from 1.6% to 25.4% in adult population. Our understanding of the genetic basis of tooth agenesis is still limited. Several genes have been explored, including, but not limited to PAX9 and MSX1. The normal function of the PAX9 gene, a transcription factor that plays an important role in signaling between epithelial and mesenchymal cells during tooth development, seems to be critical during development of dental lamina.
