Congenital Contractural Arachnodactyly

What is congenital contractural arachnodactyly?

Congenital contractural arachnodactyly is a disorder that affects many parts of the body. People with this condition typically are tall and slender with long limbs (dolichostenomelia), and have long, slender fingers and toes (arachnodactyly); joint deformities (contractures) that restrict movement; and a "crumpled" look to their ears. Additional features of congenital contractural arachnodactyly include underdeveloped muscles, abnormal curvature of the spine (scoliosis), permanently bent fingers and toes (camptodactyly), and a protruding chest (pectus carinatum). Occasionally, people with this condition have heart problems, such as enlargement of the blood vessel that distributes blood from the heart to the rest of the body (dilatation of the aorta) or leaks in one of the valves that control blood flow through the heart (mitral valve regurgitation).

A rare, severe form of congenital contractural arachnodactyly involves heart and digestive system abnormalities in addition to the typical features seen in this condition; those affected typically do not live past infancy.

How common is congenital contractural arachnodactyly?

The incidence of congenital contractural arachnodactyly is estimated to be less than 1 in 10,000.

What genes are related to congenital contractural arachnodactyly?

Mutations in the FBN2 gene cause congenital contractural arachnodactyly. The FBN2 gene provides instructions for producing the fibrillin-2 protein. Fibrillin-2 binds to other proteins and molecules to form threadlike filaments called microfibrils. Microfibrils become part of the fibers that provide strength and flexibility to connective tissue. Additionally, microfibrils hold molecules called growth factors and release them at the appropriate time to control the growth and repair of tissues and organs throughout the body. A mutation in the FBN2 gene can reduce the amount and/or quality of fibrillin-2 that is available to form microfibrils. As a result, decreased microfibril formation probably weakens the elastic fibers and allows growth factors to be released inappropriately, causing tall stature, deformities of the fingers and toes, and other characteristic features of congenital contractural arachnodactyly.

Read more about the FBN2 gene.

How do people inherit congenital contractural arachnodactyly?

This condition is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder.

In some cases, an affected person inherits the mutation from one affected parent. Other cases may result from new mutations in the gene. These cases occur in people with no history of the disorder in their family.

Where can I find information about treatment for congenital contractural arachnodactyly?

These resources address the management of congenital contractural arachnodactyly and may include treatment providers.

• Gene Review: Congenital Contractural Arachnodactyly
• MedlinePlus Encyclopedia: Arachnodactyly
• MedlinePlus Encyclopedia: Contracture Deformity
• MedlinePlus Encyclopedia: Skeletal Limb Abnormalities

You might also find information on treatment of congenital contractural arachnodactyly in Educational resources and Patient support.

Where can I find additional information about congenital contractural arachnodactyly?

You may find the following resources about congenital contractural arachnodactyly helpful. These materials are written for the general public.

• MedlinePlus - Health information (5 links)
• Educational resources - Information pages (2 links)
• Patient support - For patients and families (5 links)

You may also be interested in these resources, which are designed for healthcare professionals and researchers.

• Gene Reviews - Clinical summary
• Gene Tests - DNA tests ordered by healthcare professionals
• PubMed - Recent literature
• Online Books - Medical and science textsScriver's Online Metabolic and Molecular Bases of Inherited Disease (OMMBID):Marfan Syndrome and Related Disorders
• OMIM - Genetic disorder catalog

What other names do people use for congenital contractural arachnodactyly?

• Beals-Hecht syndrome
• Beals syndrome
• CCA
• contractural arachnodactyly, congenital

See How are genetic conditions and genes named? in the Handbook.

What if I still have specific questions about congenital contractural arachnodactyly?

• See How can I find a genetics professional in my area? in the Handbook.
• Ask the Genetic and Rare Diseases Information Center.
• Submit your question to Ask the Geneticist.

Where can I find general information about genetic conditions?

The Handbook provides basic information about genetics in clear language.

• What does it mean if a disorder seems to run in my family?
• What are the different ways in which a genetic condition can be inherited?
• If a genetic disorder runs in my family, what are the chances that my children will have the condition?
• Why are some genetic conditions more common in particular ethnic groups?

These links provide additional genetics resources that may be useful.

• Genetics and health
• Resources for Patients and Families
• Resources for Health Professionals