Osteogenesis Imperfecta

Osteogenesis imperfecta (OI), also known as fragile bone disease, is a rare inherited disorder characterized by the fact that the bone is easily broken and usually has no obvious cause. The main cause of osteogenesis imperfecta is genetic variation that produces collagen. Collagen is the main protein used for the production of connective tissue. People suffering from this disease will produce less collagen than is needed, which will cause bone development to be threatened. This can lead to deformation of the skeleton.

Imperfections in bone formation arise due to mutations in the genes encoding type I collagen chains. Type I collagen is the main protein found in bone. Hereditary inherited cases of osteogenesis imperfecta usually show very mild symptoms. However, cases are often more serious. You can also run tests such as culturing cells, observing collagen produced, and using blood samples to examine mutations in collagen-producing genes. Although these types of tests are used to some extent in the diagnosis of osteogenesis imperfecta, they are usually accurate to less than 85%.

Researchers have determined that most types of osteogenesis imperfecta are caused by the destruction or alteration (mutation) of one of the two genes (COL1A1 or COL1A2). These genes have instructions on the production of type 1 collagen. Collagen is the major protein of bone and connective tissue including skin, tendons and sclera. The COL1A1 gene is located on the long arm (q) of chromosome 17 (17q21.31 - q22). Chromosomes are present in the nucleus of all somatic cells. They have genetic characteristics of each person. The paired human chromosome is numbered from 1 to 22, the 23rd pair of X chromosome and Y chromosome is male, the female chromosome number is 2. Each chromosome has a short arm named "p", and its long arm is identified by the letter "q". The chromosome is further subdivided into numbered bands. For example, "Chromosome 17q21.31-q22" means the long arm band of chromosome 17 21.31-22.

Osteogenesis imperfecta is a genetic disorder that causes an increase in fractures and collagen defects. The main cause of this disease is the result of mutation of COL1A1 and COL1A2 genes responsible for the production of type 1 collagen. Approximately 90% of OI patients are heterozygous for mutations in the COL1A1 and COL1A2 genes. Previous studies have led to the belief that OI is an autosomal dominant disease and that there are few other mutations in the genome. However, in the past few years, autosomal recessive forms of this condition have been confirmed. The recessive morphology of OI is closely related to collagen chaperone defects responsible for procollagen production and assembly of related proteins. There is now a link to other protein defects caused by mutation to structural protein protein enzyme function.