Center for the Study of Genetic Skeletal Disorders | Brachydactyly Symphalangism and Synostoses

Brachydactyly is a general term that refers to disproportionately short fingers and toes. Brachydactyly can occur as an isolated finding, or be associated with a pattern of medical findings, called a syndrome. To date, many different forms of brachydactyly have been identified. As a group, they include shortened tubular bones in the hands and feet. Some forms may also result in short stature or affect joint function. Many types of isolated brachydactyly are inherited. X-rays can help physicians differentiate between different types of brachydactyly.

Symphalangism refers to a failure to form normal finger joints. Synosostes refer to fusions involving joints in other parts of the body.

Clinical examination and X-rays are helpful in diagnosing symphalangism and synostoses. In older children and adults, X-rays reveal bony fusions across joints. Other imaging strategies may be needed to look for altered joint formation in young children.

We found that mutations in the gene GDF5 (also called CDMP1) are one cause of brachydactyly type C. Other investigators have now identified other gene mutations that can cause brachydactyly type C. We found that mutations in the gene NOG are one cause of symphalangism and synostoses. Other investigators have now identified other gene mutations that can cause these disorders.

We are still interested in understanding how joints form and how the bones in our hands and feet are patterned. We are happy to speak with families who may be affected with brachydactyly, symphalangism, or synostoses and who are interested in helping us to identify new genes that are involved in this process.

Among the questions we want to answer are:

1. What other genes participate in the formation of joints and the patterning of our skeleton?
2. How is the fine-tuning of skeletal shape regulated?

Interested in participating?

We welcome individuals and families who are affected by brachydactyly, symphalangism, or synostoses to participate in our research by contacting us.

Physicians seeking assistance in making a diagnosis for brachydactyly, symphalangism, or synostoses are also welcome to contact us.