Faulty collagen synthesis causing hyperextensible skin, tendency to bleed (easy bruising), and hypermobile joints.- Multiple types.- Inheritance and severity vary.- Can be autosomal dominant or recessive.

- May be associated with joint dislocation, berry and aortic aneurysms, organ rupture.

- Hypermobility type (joint instability): most common type.- Classical type (joint and skin symptoms): caused by a mutation in type V collagen (eg, COL5A1, COL5A2).- Vascular type (fragile tissues including vessels, muscles, and organs that are prone to rupture): deficient type III procollagen.