Book Syndrome
Book syndrome is a very rare type of ectodermal dysplasia. Signs and symptoms include premolar aplasia (when the premolars fail to develop); excessive sweating (hyperhidrosis); and premature graying of the hair. Other features that have been reported in only one person include a narrow palate (roof of the mouth); hypoplastic (underdeveloped) nails; eyebrow anomalies; a unilateral simian crease; and poorly formed dermatoglyphics (skin patterns on the hands and feet). Book syndrome is inherited in an autosomal dominant manner.