Atelosteogenesis Type 2

Atelosteogenesis type 2 (AO2) is a severe skeletal disorder affecting cartilage and bone development. Affected infants have very short arms and legs, a narrow chest, prominent rounded abdomen, distinctive facial features, cleft palate, clubfoot, and severe respiratory complications. Infants with AO2 are usually stillborn or die shortly after birth due to severe respiratory failure. Some infants have lived for a short time with intensive medical support. AO2 is caused by pathogenic variants in the SLC26A2 gene.

AO2 is inherited in an autosomal recessive manner. This type of inheritance requires the presence of two copies of a pathogenic variant in the gene for a person to have the genetic disease. Both parents must be carriers of a pathogenic variant in the gene in order to be at risk to have an affected child. The child must inherit a pathogenic variant from each carrier parent in order to be affected. There is a 1 in 4 chance that a baby will inherit two mutated copies of the gene and be affected when both parents are carriers.

There are generally no signs or symptoms associated with being a carrier for AO2. However, the risk to have a child affected with AO2 is increased. Testing of reproductive partners is recommended for carriers of AO2.

Atelosteogenesis type 2 is extremely rare and the occurence of the condition is unknown. This condition is more commonly seen in Finland.

Genetic Home Reference: Atelosteogenesis type 2 (http://ghr.nlm.nih.gov/)

OMIM: [256050. ATELOSTEOGENESIS, TYPE II; AOII] (http://www.ncbi.nlm.nih.gov/omim)
Gene Reviews: Atelosteogenesis type 2 (http://www.ncbi.nlm.nih.gov/books/NBK1116/)

• Full gene sequencing