Figure 1. Pedigree and dental/radiographic features of the phenotype. The four-generation pedigree includes 27 persons (top). The 23 people enrolled in the study are indicated by an asterisk. Oral photographs are shown from three affected individuals (III-4, III-9, IV-2) and one unaffected (IV-1). Radiographs for III-4 and III-9 are shown below their oral photos. Individual III-4 (age 30 yrs) has a mild gray discoloration to her teeth. Her panorex shows thistle-tube pulp chambers. Individual III-9 (age 23 yrs) has more severe discoloration, which is still evident in her lower anterior teeth. All of the maxillary anterior teeth were veneered for esthetic reasons. Bitewing radiographs of the primary teeth, taken at age 5 yrs, show pulpal obliteration and accelerated attrition. An anterior periapical survey, taken at age 17 yrs, shows bulbous crowns and pulpal obliteration. The primary teeth of affected individual IV-2 at age 2 yrs show amber discoloration and coronal translucency, in contrast to the normal dentition of individual IV-1 at age 3 yrs.