Identifying polymorphism in enamelin gene in amelogenesis imperfecta (AI)

Amelogenesis imperfecta (AI) is a developmental defect of dental enamel formation. This enamel defect can be caused by mutation in ENAM gene. Hence this study investigated the molecular defect in the enamelin gene in a patient with the clinical features of AI. The genomic DNA was extracted from patient's whole blood samples and the DNA was subjected to the polymerase chain reaction (PCR) in the presence of 16 pairs of oligonucleotide primers specifically designed to amplify all the 10 exons, g2382, g6395 and g8344 of the enamelin (ENAM) gene in the long arm of the chromosome 4. The PCR products were gel purified and sequenced to identify any mutation. The ENAM gene sequences from the patient were aligned with the reference sequence (GenBank accession no. AY167999) using VectorNTI software. We identified a single base difference at location g359 A-->G on exon 1 between the reference sequence and patient's sequence. We successfully ruled out any possible mutation on exon 2, exon 3, exon 4, exon 5, exon 6, exon 7, exon 8, exon 9, exon 10, g2382, g6395 and g8344.