Brachyolmia: an autosomal dominant form.

We have investigated a mother and son of South African Xhosa stock who presented with short-trunk dwarfism and kyphoscoliosis. Radiographs show the marked platyspondyly and vertebral irregularity characteristic of brachyolmia. Our patients provide further evidence for the existence of an autosomal dominant form and supports the theory of heterogeneity in this rare group of genetic skeletal disorders. Molecular investigations in this South African family are currently underway but at present the basis defect of brachyolmia remains unknown.