What Causes OI? The dominant mutations happen on the gene COL1A1 or COL1A2 gene Recessive mutation occur on (CRTAP) gene or the LEPRE1 gene Mutation on chromosome 17 OI is caused by an abnormal production of collagen. Collagen structural protein material for bones, skin, cartilage, and ligaments.
Types of OI OI was thought to have been dominant autosomal, but research has found types of recessive OI as well.
Type I This is the most common form of OI It’s dominant autosomal Least severe Have normal or near-normal height Loose joints, weak muscles Whites of highs have blue, purple, or gray tint Some or no bone deformity Possible curved spine Possible hearing loss Normal collagen, less than normal amount
Type II Most severe Most people with this type die soon after birth Many times fatalities caused by deformed lungs Many fractures, severe bone deformity Small stature Whites of eyes tinted Collagen not formed properly Dominant autosomal
Type III Easily fractured bones, some occurring before birth, some healed before birth Short stature Whites of eyes tinted Loose joints and muscle development poor in limbs Curved spine Possible respiratory problems severe deformed bones Brittle teeth and hearing loss possible Collagen not formed properly Dominant Autosomal
Type IV Less severe than type III Fragile bones, fracture often Below average stature Eye whites have little or no tint Some bone deformity, not severe Tendency toward curved spine Ribs are barrel-shaped Could have brittle teeth and weak hearing Collagen not formed properly Dominant autosomal
Type V Similar to IV in symptoms and clinically Large calluses Forearm rotation restricted Whites of eyes normal Normal teeth Dominant pattern This type is caused by unidentified mutations Don’t have mutations in type I collagen genes
Type VI Similar to type IV in symptoms and clinically Activity of alkaline phosphatase is elevated Unknown whether it’s dominant or recessive, but most likely recessive By 2007, only 8 people had been diagnosed with this type of OI
Type VII Could be like type IV Could be like type II, but with normal eye whites Below average stature Short arm bone Short upper leg bone Coxavera is possible Recessive autosomal Caused by CRTAP gene
Type VIII could be like type II Could be like type III Normal whites of eyes Growth deficiency is very severe Deficiency of PH31 Recessive autosomal Caused by LEPRE1 gene
Treatment There is no known cure for OI There are treatments to help symptoms of OI Making sure bones are as healthy as possible is important Surgical and dental procedures as well as physical therapy may be recommended “Rodding Surgery” which is done by putting metal rods next to long bones to strengthen them and prevent deformity
Impact on people with OI Since severity differs most live life normally, and others have problems Some have deformity of limbs and other parts of the body which could make mobility limited Some just have fragile bones Some have tinted eyes Some have hearing problems or are deaf Some don’t live long after their born (type II) Most of them live happy successful lives like anyone else
Research Outlook Many different types of research are being done although researchers seem like they’re looking for different treatments rather than cures right now The research includes looking at the affects of vibration therapy, Tariperatide (in adults), Bisphosphonates, and other treatments. There is hope for a cure, but not soon, right now treatments are the main focus
Myth Busters(AKA two extra interesting facts! :D) Myth: Babies with OI should be carried around with a pillow and discouraged from moving. Truth: It’s good to take precautions, but it makes it so the baby doesn’t discover movement naturally. Also immobility leads to loss in bone mass which would cause more problems
Myth Busters (continued) Myth: If a parent has OI, so will their child Truth: It could either be a dominant or recessive trait. If one parent has dominant OI, there is a 50% chance their child will get it. If it’s recessive, the child has a 25% chance they’ll be affected and a 50% chance of being a carrier