THE GENE FOR ACHONDROPLASIA MAPS TO THE TELOMERIC REGION OF CHROMOSOME 4P

Achondroplasia is the most common type of genetic dwarfism. It is char acterized by disproportionate short stature and other skeletal anomali es resulting from a defect in the maturation of the chondrocytes in th e growth plate of the cartilage. We have now mapped the achondroplasia gene near the telomere of the short arm of chromosome 4 (4p16.3), by family linkage studies using 14 pedigrees. A positive lod score of z=3 .35 with no recombinants was obtained with an intragenic marker for ID UA. This localization wilt facilitate the positional cloning of the di sease gene.