Analysis of AXIN2 gene mutations in a family with isolated oligodontia

To investigate the mutational characteristics of AXIN2 gene in a family affected by non-syndromic oligodontia and to provide a molecular basis for studying the pathogenesis of oligodontia.

A family of different descents with oligodontia, and some unrelated healthy controls were enrolled in our study. Genomic DNA was isolated from blood samples. Mutation analysis was performed by amplifying AXIN2 exons as well as their exon-intron boundaries and sequencing the products.

DNA sequencing of AXIN2 gene revealed 3 mutations in the 2 patients with oligodontia: a homozygotic silent mutation c. Of which 1 mutation 365A > G (p.Pro455 =) was in exon 3, and 2 mutations c.956 + 16A > G(Ⅱ-1: homozygosis; Ⅲ-1: heterozygosis) plus c.1200 + 71A > G (homozygosis) were in intron, which were possibly contributed to the structural and functional changes of proteins. Meanwhile, the heterozygotic mutations (c.1365A > G and c.1200 + 71A > G) were found in proband's mother (Ⅱ-2).

Our finding suggests the c.956 + 16A > G, c.1365A > G and c.1200 + 71A > G mutations of AXIN2 may be responsible for oligodontia phenotype in this Chinese family, certainly, an understanding of the exact function of AXIN2 in odontogenesis requires further detailed analysis of each stage of this process.