Metachondromatosis is an autosomal dominant, incompletely penetrant genetic disease affecting the growth of bones, leading to exostoses primarily in the hands and feet as well as enchondromas of long bone metaphyses and iliac crests. This syndrome affects mainly tubular bones, though it can also involve the vertebrae, small joints, and flat bones. The disease is thought to affect exon 4 of the PTPN11 gene. Metachondromatosis is believed to be caused by an 11 base pair deletion resulting in a frameshift and nonsense mutation. The disease was discovered and named in 1971 by Pierre Maroteaux, a French physician, when he observed two families with skeletal radiologic features with exostoses and Ollier disease. The observation of one family with five affected people led to the identification of the disease as autosomal dominant. There have been less than 40 cases of the disease reported to date. Signs and Symptoms
Metachondromatosis is identified by the presence of both multiple enchondromas and osteochondromas in the patient, although other less characteristic symptoms are often associated with the disease. The symptoms usually become apparent in the first 10 years of life and disappear later in life. The symptoms of Metachondromatosis are seen as follows:

Enchondromas
Enchondromas are benign tumors present on the inside of bones. In Metachondromatosis, enchondromas involves the iliac crests and metaphyses of long bones, often the proximal femur. Usually, these tumors are painless; however, when present in the hands or feet, or in multiple lesions, as typically seen, bone deformity can occur.
Marketing
The marketing of the Claritin brand is important in the history of direct-to-consumer advertising of drugs.The first television commercial for a prescription drug was broadcast in the United States in 1983, by Boots. It caused controversy. The federal Food and Drug Administration responded with strong regulation requiring disclosure of side effects and other information. These rules made pharmaceutical manufacturers balk at spending money on ads that had to highlight negative aspects.In the mid-1990s, the marketing team for Claritin at Schering-Plough found a way around these rules. They created brand awareness commercials that never actually said what the drug was for, but instead showed sunny images, and the voiceover said such things as "At last, a clear day is here" and "Its time for Claritin" and repeatedly told viewers "Ask your doctor [about Claritin]." The first ads made people aware of the brand and increased prescriptions, which led Schering-Plough and others to aggressively pursue the advertising strategy.In 1998, a 12-page one-shot comic based in the Batman: The Animated Series was given away to advertise Claritin. The book, written by PRIEST, penciled by Joe Staton, and inked by Mike DeCarlo, sees Tim Drake unable to perform his crime-fighting duties because hay fever and antihistamines make him drowsy. After being given a prescription for Claritin, he saved Batman from Poison Ivy.This trend, along with advice from the Food and Drug Administrations attorneys that it could not win a First Amendment case on the issue, prompted the administration to issue new rules for television commercials in 1997.