Osteogensis Imperfecta (OI)

“Brittle bone disease”

• Congenital Disease: present at birth• Caused by defect in the gene that makes type 1 collagen– Major strucutural protein that helps with the structure of

bones, ligaments, and other connective tissue– The type of OI depends on the specific mutation of the

gene• If you have one copy of the gene then you will get it, which

means most cases are inherited from parents but some are created by new genetic mutations (50% chance of passing it on)

• No cure but there are treatments such as bisphosphonates, casts/braces, and exercise. There are also some surgical treatments that include rods or fusions.

Symtoms

• Weak bones- prone to fractures and breaks• Short stature• Multiple fractures• Blue tint to the whites around the eye (blue

sclera)• Hearing loss• Bone deformities• Brittle teeth

Types• Type I

– Most common and mildest– Collagen structure is normal but there isn’t as much as there should be

• Type II– Most severe– Collagen doesn’t form properly– Sometimes bones even break when in the womb so many infants with OI don’t

survive• Type III

– Improperly formed collagen– Severe bone deformities (such as spinal cord)– Loose joints and poor muscle development

• Type IV– Moderately severe– Improperly formed collagen– Deformities are mild to moderate

OI Type V

Child

Adult

Normal