Osteogenesis Imperfecta [OI] is a genetic disorder. The typical symptoms of OI are bones that seem to break very easily. This can happen when there is very little impact or even no apparent cause. There are actually several different types of OI that have been discovered and these are used describe how severely the genetic disorder is in any given individual. People with Osteogenesis Imperfecta may end up suffering several hundred fractures over the course of a lifetime.
Statistics on Osteogenesis Imperfecta
1. Type I Osteogenesis Imperfect occurs in 1 out of 30,000 live births.
2. Type II forms of this genetic disorder occur in 1 out of 60,000 live births.
3. Type III happens in 1 out of 70,000 live births.
4. All other forms of OI are considered to be quite rare.
5. A higher incidence of Osteogenesis Imperfecta has been observed in 2 major tribal groups in Zimbabwe.
6. No known differences based on gender exist for the development of OI.
7. All cases of OI have an onset period that occurs either in utero or during infancy. Only rare cases begin after a child enters the toddler age bracket.
8. If an affected parent has the disease, generally there is a 50% chance they will pass the condition on to their child.
9. Type III OI accounts for 20% of the total known cases and is characterized by bones that are easier to bend and fracture. Many children do not survive to adulthood with this type of OI.
10. An ultrasound may be used during pregnancy to detect limb abnormalities from Osteogenesis Imperfecta at 15-18 weeks gestation.
11. Type II is the most lethal form of Osteogenesis Imperfecta and accounts for 10% of all known cases of the genetic disorder.
12. This condition affects an estimated 6 to 7 per 100,000 people worldwide.
13. Types I and IV are the most common forms of Osteogenesis Imperfecta, affecting 4 to 5 per 100,000 people.
14. Mutations in the COL1A1 and COL1A2 genes are responsible for more than 90% of all cases of OI.
15. About 25% of infants with OI type IV are born with bone fractures.
16. Infants with Type II have bones that appear bent or crumpled and fractured before birth. Most infants with Type II OI are stillborn or die shortly after birth because of breathing failure.
17. In the milder forms of OI, 25-30% of cases occur as a result of new mutations.
18. Type I cases account for 60% of all OI cases.
19. There is a 7x greater incidence of an overall fracture rate in individuals affected by OI when compared to the general population.
20. People with Osteogenesis Imperfecta are left with only 70% vertebral bone mineral content in adults.
Understanding the Disease
Osteogenesis Imperfecta in the classic sense affects how much Type I collagen is produced or it will affect the type of collagen that is created. Because collagen is the major protein involved in the connective tissues of the body, the OI genetic defect winds up undermining the framework of what the bones are formed around. In recessive versions of this disorder, the genes will actually interfere with the production of collagen.
The clinical features of OI often make it possible to diagnose it. Molecular diagnostics or biochemical testing can help to confirm a diagnosis in some instances as well. Most of these tests take several weeks to confirm, but in return, 90% of all Type I mutations can be discovered. What can make OI difficult to diagnose is the fact that not all characteristics of the genetic disorder are evident in every case. With eight known types of Osteogenesis Imperfecta and the fact that only one copy of the mutation carrying gene is required for child to have this disorder, it can be an inherited disease or it may occur spontaneously.
By knowing the statistics of Osteogenesis Imperfecta, it becomes possible to seek treatment for this disorder if necessary. There is no known cure for this genetic disorder, so treatments are directed toward the prevention of symptoms while maximizing the ability to move about independently. Wheelchairs and other devices that are designed to assist with mobility are frequently prescribed. Parents of children who have Osteogenesis Imperfecta are encouraged to design home environments that are flexible instead of rigid to further prevent fractures from occurring.
Impact on Health
Osteogenesis Imperfecta may greatly affect the child’s life, steps can be taken to help make that like are comfortable. Because genetic disorder can be so variable, the mortality and morbidity rates are also very variable.
The good news is that there is a normal life expectancy in the most common forms of Osteogenesis Imperfecta. Even in Type IV cases of OI, like expectancy is only slightly reduced when compared to the general population. In the more severe cases of OI, one of the most common issues faced involve having bones break through the normal breathing process. This is why the mortality and morbidity rates of Type II and Type III Osteogenesis Imperfecta are deadly.
Even if genetic treatments and gene therapy become available to medical science, treatments for Osteogenesis Imperfecta may be difficult because of the fact that the mutations which cause this disorder are dominant negative. For the foreseeable future, treatment options will involve using technology to help make people mobile and protected, while certain drug therapies are being looked at to help reinforce bone structure and build strength.
The prognosis for person who is born with Osteogenesis Imperfecta depend on the severity of their symptoms. Even though people with this disorder have many fractures, are restricted from certain physical activities, and tend to be shorter in stature, many go on to lead accessible and productive lives. People with Osteogenesis Imperfecta can raise families, attend school, and even participate in certain sports and recreational activities. They are active members of their communities, proving that a genetic disorder does not need to hold someone back from happiness.