Joubert syndrome: review and report of seven new cases.

Joubert syndrome (JS) is an autosomal-recessive disorder, characterized by hypotonia, ataxia, global developmental delay and molar tooth sign on magnetic resonance imaging. A variety of other abnormalities have been described in children with JS, including abnormal breathing, abnormal eye movements, a characteristic facial appearance, delayed language, hypersensitivity to noise, autism, ocular and oculomotor abnormalities, meningoencephaloceles, microcephaly, low-set ears, polydactyly, retinal dysplasia, kidney abnormalities (renal cysts), soft tissue tumor of the tongue, liver disease and duodenal atresia. Even within siblings the phenotype may vary, making it difficult to establish the exact clinical diagnostic boundaries of JS. We review the clinical characteristics of seven cases that fulfill the criteria of JS.