The mutation of COL2A1 gene leads to abnormal skeletal growth and problems with hearing and vision.

What characterizes Kniest dysplasia from other type II osteochondrodysplasia is the level of severity and the dumb-bell shape of shortened long tubular bones.

Because collagen plays an important role in the development of the body, people with Kniest Dysplasia will typically have their first symptoms at birth.

[7] Studies have shown that a mutated COL2A1 gene is responsible for all type II chondrodysplasias, including Kniest dysplasia.

It is believed that point mutations or the alteration of splice sites in COL2A1 domains will result in Kniest Dysplasia.

Two key features to look for in a patient with Kniest dysplasia is the presence of dumb-bell shaped femur bones and coronal clefts in the vertebrae.

[citation needed] A recent article in 2015 reported a persistent notochord in a fetus at 23 weeks of gestation.

Hypochondrogenesis is caused when type II collagen is abnormally formed due to a mutation in the COL2A1 gene.

This is the first time that researchers found a persistent notochord in a human body due to a COL2A1 mutation.