Table I.

Human genetic skeletal diseases result from qualitative (anti-morphic) defects in cartilage structural proteins.

Gene	Protein	Disease(s)	Genetic loci	Domain	Refs.
COMP	COMP	Pseudoachondroplasia (AD) Multiple epiphyseal dysplasia (AD)	PSACH EDM1	T3-7 repeats C-terminal domain	(4,45)
MATN3	Matrilin-3	Multiple epiphyseal dysplasia (AD)	EDM5	vWFA	(18)
COL9A1 COL9A2 COL9A3	Type IX collagen	Multiple epiphyseal dysplasia (AD)	EDM6 EDM2 EDM3	COL3 domain	(46–48)
COL2A1	Type II collagen	Diverse range of AD and AR phenotypes collectively known as type II collagenopathies	Various	Triple helical region and C-propeptide	(49)
COL11A1 COL11A2	Type XI collagen	Diverse range of AD and AR phenotypes collectively known as type XI collagenopathies	Various		(50)
COL10A1	Type X collagen	Metaphyseal chondrodysplasia, type Schmid (AD)	MCDS	Carboxyl-terminal non-collagenous domain (NC1)	(51)
ACAN	Aggrecan	Spondyloepimetaphyseal dyslasia (AR) Osteochondritis dissecans (AD) Short stature, accelerated bonematuration (AD)	SEMD OCD	G3 C-type lectin domain	(52–54)

COMP, cartilage oligomeric matrix protein; PSACH, pseudoachondroplasia; AD, autosomal dominant; AR, autosomal recessive.