SNP Shot: Genomic Insights

Melorheostosis is an uncommon skeletal disorder where extra bone tissue develops on the surface of existing bones. X-ray images reveal a distinctive "flowing" pattern, reminiscent of dripping candle wax. This excessive bone growth usually affects the bones of a single arm or leg but can also involve the pelvis, sternum, ribs, or other bones. The name "melorheostosis" comes from Greek words meaning limb ("melos"), flow ("rheos"), and bone formation ("ostosis"). The extra bone growth is benign, meaning it's not cancerous and doesn't spread.

Symptoms of melorheostosis typically manifest during childhood or adolescence. Individuals may experience persistent (chronic) pain, permanent joint stiffness (contractures), and reduced movement in the affected area. The limb may appear thicker or larger, and the skin above the affected bone can become red, thickened, and glossy.

Melorheostosis can be a component of Buschke-Ollendorff syndrome, another rare condition. Buschke-Ollendorff syndrome involves skin growths called connective tissue nevi and increased bone density called osteopoikilosis. A small number of those with Buschke-Ollendorff also have melorheostosis or other skeletal abnormalities. Initially, it was thought that isolated melorheostosis might share a genetic basis with Buschke-Ollendorff syndrome. However, research has shown that mutations in different genes cause Buschke-Ollendorff syndrome and melorheostosis that occurs independently. Therefore, they are now classified as distinct conditions.

Inheritance:

Melorheostosis is not an inherited condition and cannot be transmitted from parents to children. It results from somatic mutations within bone cells that arise during a person's life.