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Typically Nager acrofacial dysostosis (NAFD) comprises two groups of defects involving respectively the limbs and craniofacial region. The former are mainly deficiencies mostly affecting upper limbs. The latter form a complex indistinguishable from mandibulofacial dysostosis (MFD). The prevalence is unknown; about 70 cases of Nager syndrome have been published. The MFD complex is unmistakable and comprises downward slant of palpebral fissures, ptosis of upper lids, coloboma of lower lids, deficiency of eyelashes of the medial one-third to two-thirds of the lower eyelids, hypoplasia of the malar eminences and zygomata, hypoplasia of maxilla with cleft of secondary palate or highly-arched palate, absence of velum (rarely with chonal atresia), extension of a ``tongue`` of temporal hair down the sides of the cheeks; clefts of lip are rare. Hypoplasia or absence of thumbs is the most characteristic feature almost invariably associated with radio-ulnar synostosis. Triphalangeal thumbs and index finger are equally characteristic. Most NAFD individuals have normal eyes and intelligence, and after infancy most are healthy and are presumed to have a normal lifespan. All acrofacial dysostosis must be considered as genetic disorders until proven otherwise, and parents deserve careful scrutiny for mild manifestations. |