Questions and answers about heritable disorders of connective tissue - Health Topics - Pamphlet

Pamphlet by: Nat'l Inst. of Arthritis and Musculoskeletal & Skin Diseases, July 1, 2001

The National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), a part of the National Institutes of Health (NIH), is the lead Federal agency for connective tissue research. Several other NIH institutes are also studying HDCTs. The NIAMS supports research through grants to scientists around the country, in national and international clinical trials, and at the NIH campus itself. Here is some of the research that is being done:

* The NIAMS is conducting an in-depth natural history study of people who have Marfan syndrome (which leads to abnormally long bones), nail-patella syndrome (a congenital skeletal disorder), Stickler syndrome (which causes eye and joint problems), and Ehlers-Danlos syndrome (which causes skin and blood vessel problems). All of these disorders have multiple, interrelated symptoms. NIAMS scientists are studying these people closely and over a long period to get a more complete picture of the diseases. They hope to improve their understanding of the genetic origins of the symptoms, of disease progression, and of mutations in patients and their relatives. Scientists expect their findings to apply to other HDCTs as well.

* The NIAMS is supporting a study looking for ways to treat diseases such as osteogenesis imperfecta by using gene therapy. Stem cells, which have the potential to develop into more specialized cells, would replace bone cells that have gene defects. This research is being conducted on specially bred mice.

* Another NIAMS project is examining gene defects that lead to abnormal elastin, the connective tissue protein that allows arteries, muscles, and other organs to respond in certain ways to movement. So far, the investigators have shown how elastin gene mutations cause two specific diseases: a skin disease (cutis laxa) and a blood vessel disease (supravalvular aortic stenosis). Scientists hope to learn more about how mutations affect elastin fiber and tissue growth. They also hope to find out how gene defects lead to the development of elastin disease.

* The NIAMS is encouraging the establishment of new research registries for connective tissue disorders and other conditions. These registries would support the collection of demographic and medical data from patients and families to be used in research on disorders. Epidermolysis bullosa is one of the disorders for which the Institute has already established a research registry.

Other NIAMS researchers are exploring

* the chemistry and biology of elastin genes

* collagen gene defects (several types) that cause bone diseases

* collagen IV gene defects in mice and in humans (Alport syndrome)

* proteoglycans, a group of proteins that maintain tissue stiffness

* fibroblasts, cells that form the fibrous tissues in the body

* cartilage, joints, and skin layers.

Ongoing studies of aneurysms--a weak spot in a blood vessel wall that threatens to burst--are taking place at several NIH Institutes. Aneurysms can prove deadly to people with Marfan syndrome and other HDCTs. These studies have been helped by a pioneering project at the NIAMS that developed a breed of mice prone to aneurysms. Scientists hope the mutant mice will improve understanding of aneurysms and ways to prevent them.