There are various types of chondrodysplasias, which affect growth of bone and cartilage.
- Achondroplasia is a relatively common cause of dwarfism, occurring in perhaps 1 in every 25,000 births. Most cases are due to a new mutation in the fibroblast growth factor receptor 3 gene FGFR3. Unlike some forms of dwarfism, achondroplastic dwarfism is not curable with growth hormone.
- Conradi-Hunermann syndrome, also known as X-linked dominant chondrodysplasia punctata, is caused by defects in the EPB gene. The following SNPs may be related to this or other types of chondrodysplasia:
- rs743616 in the arylsulfatase A (ARSA) gene
- rs28935474 in the arylsulfatase E (ARSE) gene on the X chromosome, also known as P578S, is recessive, according to OMIM 300180.0007
- rs1065757 in the arylsulfatase B (ARSB) gene on chromosome 5 may be associated with chondrodysplasia punctata
- rs2819590 in the SUMF1 gene may be related to chondrodysplasia punctata
- Jeune syndrome is an extremely rare but severe recessive disorder that causes death in infancy or early childhood. It is also known as asphyxiating thoracic dystrophy. Jeune syndrome is a ciliopathy caused by mutations in the IFT80 gene.
- Rhizomelic chondrodysplasia punctata type 1 (RCDP1) is caused by mutations in the PEX7 gene. The following SNP related to RCDP1 is tested by 23andMe:
- i3002517, also known as L292X (risk genotype AA)