3.4 | Phenotypes of NSTA patients with EDA1mutations at codon 289
Two EDA1 mutations (c.865C>T and c.866G>A) at codon 289 were reported in our study as well as in previous studies (Table 3, (Lee et al., 2014; Ruiz-Heiland et al., 2016; Song et al., 2009)). The p.Arg289Leu and p.Arg289Cys mutations caused a change from a positively-charged residue to a non-polar residue. Although the Arg289His mutation did not cause a change in physicochemical properties, the volume of the side chain decreased. Phenotype analysis shows that reported mutations at codon 289 of EDA1 affects the lateral incisors (100%, 91.7%), the mandibular central incisors (91.7%), and the mandibular second premolars (75.0%). However, the second molars (8.3%), mandibular first molars (16.7%), and maxillary central incisors (16.7%) are less affected. It is particularly interesting that maxillary first molars are present in all patients (Figure 5).