chondrodysplasia with joint dislocations, gPAPP type

Chondrodysplasia with joint dislocations, gPAPP type is a condition that affects the development of the bones and joints. It is associated with changes in the BPNT2 gene, which plays a key role in skeletal development. The condition typically presents in early childhood, and affected individuals show characteristic features such as a cleft palate, micrognathia, and patellar dislocation. This condition is very rare, affecting fewer than one in a million people.

The clinical presentation of chondrodysplasia with joint dislocations, gPAPP type is primarily marked by facial and skeletal abnormalities. Characteristic features always observed include a cleft palate, micrognathia, and patellar dislocation, which often lead to early medical evaluation. In addition, many individuals may exhibit features such as brachydactyly, short metacarpals, flat facial appearance, and short stature, while others can also show findings like capitate-hamate fusion, knee dislocation, and limited elbow extension. Not all individuals experience all features, and severity varies considerably.

This condition is caused by alterations in the BPNT2 gene. The BPNT2 protein is involved in critical cellular pathways that affect cartilage and bone development, and disruptions in its function can lead to abnormal skeletal formation. It is inherited in an autosomal recessive manner, meaning that an individual must inherit two altered copies of the gene, one from each parent, to be affected. This condition is more common when parents share a common ancestor, as the likelihood of both carrying the same rare genetic variant increases. Affected families are encouraged to seek genetic counseling to discuss inheritance patterns and implications for family planning. Associated genes include BPNT2.