CASE OF RING CHROMOSOME-7 - THE 1ST REPORT OF NEUROPATHOLOGICAL FINDINGS

We report on a boy with ring chromosome 7 who had severe mental retard ation, growth failure, microcephaly, cleft lip and palate, cafe-au-lai t spots, nevus flammeus, and genital abnormalities, and died of pneumo nia at age 20 months. On autopsy he had fusion of the anterior cerebra l hemispheres, accompanied by agenesis of olfactory bulbs and tracts, closely resembling those found in semilobar holoprosencephaly. In addi tion, heterotopic Purkinje cell clusters in the cerebellar white matte r, absence of pigmentation within the brainstem pigmented neurons, and severe hypomyelination in the whole brain were noted. The patient may represent the most severe manifestation of ring chromosome 7, and thi s is the first detailed neuropathological report on this subject. (C) 1993 Wiley-Liss, Inc.