Hypodontia and Cleft Lip Palate; A Consequence of Homozygous Missense Mutation in PAX9 Gene

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Research Paper 01/03/2017
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Hypodontia and Cleft Lip Palate; A Consequence of Homozygous Missense Mutation in PAX9 Gene

Agha Muhammad Raza, Nasrullah Mengal, Muhammad Nawaz, Muhammad Saeed, Abdul Wali, Jamil Ahmad
Int. J. Biosci.10( 3), 382-387, March 2017.
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The congenital absence of teeth is one of the major and commonest dental developmental disorders seen in humans. Hypodontia is used as a collective term for congenitally absence of one to six teeth, excluding the third molars. The knowledgeof the etiological basis of inherited tooth loss remains poor,thus far two genes (PAX9 and MSX1) have been identified as the major causes of hypodontia.Here, we investigated two Pakistani families affected with hypodontia and cleft lip palate. Radiographic examination revealed missing of multiple permanent teeth in affected individuals of both families. Blood samples (5ml) were collected from all affected individuals, their parents and normal siblings. Genomic DNA was extracted by using inorganic method. All the three coding exons of PAX9(NM_006194) were amplified and sequenced. Sequencing of the PAX9 coding exons and splice sites showed a homozygous missense substitution in exon 3 (c. 718C>G; p.Ala240Pro) in the affected individuals of both the families. This mutation co-segregated with hypodontia and cleft lip palate in the respective families. As a conclusion, we identified a missense substitution (p.Ala240Pro) in gene PAX9 in two different Pakistani families with hypodontia and cleft lip palate.


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