The "CHIME" syndrome (MIM#280000) is a rare neuroectodermal disorder comprised of Colobomas of the eye, Heart defects, Ichthyosiform dermatosis, Mental retardation, and Ear defects. We report on the sixth child with this syndrome and the first of these to develop acute lymphoblastic leukemia at age 4 1/2 years. Her major problems included a migratory ichthyosiform dermatosis, multiple skin infections and infestations, bilateral retinal coloboma, developmental delay, seizures, infantile macrosomia, facial anomalies, a duplicated renal collecting system, and conductive hearing loss. Histologic examination of the skin demonstrated findings of an epidermal nevus with deep rete pegs, hyperkeratosis, and a markedly increased granular layer. The cause of the CHIME syndrome is unknown, but the disorder is easily recognized because of the striking phenotype. The diagnosis is important to make because of the potential for associated congenital heart disease, neurologic compromise, possible autosomal recessive inheritance, and possible association with malignancy.