We have identified a novel developmental disorder with complex phenotypic characteristics involving primarily the nervous system, which appears to be common in a specific Gypsy group in Bulgaria. We propose to refer to the syndrome as congenital cataracts facial dysmorphism neuropathy (CCFDN). We have assigned the disease locus to the telomeric region of chromosome 18q. Linkage disequilibrium and highly conserved haplotypes suggest genetic homogeneity and founder effect. CCFDN co-localises with an EST which shows high homology to a conserved Drosophila gene involved in the regulation of nervous system development in vertebrates.