Distal arthrogryposis type 1 is a disorder characterized by joint deformities (contractures) that restrict movement in the hands and feet. The term "arthrogryposis" comes from the Greek words for joint (arthro-) and crooked or hooked (gryposis). The characteristic features of this condition include permanently bent fingers and toes (camptodactyly), overlapping fingers, and a hand deformity in which all of the fingers are angled outward toward the fifth finger (ulnar deviation). Clubfoot, which is an inward- and upward-turning foot, is also commonly seen with distal arthrogryposis type 1. The specific hand and foot abnormalities vary among affected individuals. However, this condition typically does not cause any signs and symptoms affecting other parts of the body.

Distal arthrogryposis type 1 affects an estimated 1 in 10,000 people worldwide.

Distal arthrogryposis type 1 can be caused by mutations in at least two genes: TPM2 and MYBPC1. These genes are active (expressed) in muscle cells, where they interact with other muscle proteins to help regulate the tensing of muscle fibers (muscle contraction). It is unclear how mutations in the TPM2 and MYBPC1 genes lead to the joint abnormalities characteristic of distal arthrogryposis type 1. However, researchers speculate that contractures may be related to problems with muscle contraction that limit the movement of joints before birth.

In some cases, the genetic cause of distal arthrogryposis type 1 is unknown. Researchers are looking for additional genetic changes that may be responsible for this condition.

Genetic Testing Information

• Genetic Testing Registry: Arthrogryposis, distal, type 1A

Genetic and Rare Diseases Information Center

• Distal arthrogryposis type 1

Patient Support and Advocacy Resources

• National Organization for Rare Disorders (NORD)

Clinical Trials

• ClinicalTrials.gov

Catalog of Genes and Diseases from OMIM

• ARTHROGRYPOSIS, DISTAL, TYPE 1A; DA1A

Scientific Articles on PubMed

• PubMed

• Bamshad M, Bohnsack JF, Jorde LB, Carey JC. Distal arthrogryposis type 1: clinical analysis of a large kindred. Am J Med Genet. 1996 Nov 11;65(4):282-5. doi: 10.1002/(SICI)1096-8628(19961111)65:43.0.CO;2-R. Citation on PubMed
• Bamshad M, Jorde LB, Carey JC. A revised and extended classification of the distal arthrogryposes. Am J Med Genet. 1996 Nov 11;65(4):277-81. doi: 10.1002/(SICI)1096-8628(19961111)65:43.0.CO;2-M. Citation on PubMed
• Beck AE, McMillin MJ, Gildersleeve HI, Kezele PR, Shively KM, Carey JC, Regnier M, Bamshad MJ. Spectrum of mutations that cause distal arthrogryposis types 1 and 2B. Am J Med Genet A. 2013 Mar;161A(3):550-5. doi: 10.1002/ajmg.a.35809. Epub 2013 Feb 7. Citation on PubMed or Free article on PubMed Central
• Gurnett CA, Desruisseau DM, McCall K, Choi R, Meyer ZI, Talerico M, Miller SE, Ju JS, Pestronk A, Connolly AM, Druley TE, Weihl CC, Dobbs MB. Myosin binding protein C1: a novel gene for autosomal dominant distal arthrogryposis type 1. Hum Mol Genet. 2010 Apr 1;19(7):1165-73. doi: 10.1093/hmg/ddp587. Epub 2010 Jan 2. Citation on PubMed or Free article on PubMed Central
• Sung SS, Brassington AM, Grannatt K, Rutherford A, Whitby FG, Krakowiak PA, Jorde LB, Carey JC, Bamshad M. Mutations in genes encoding fast-twitch contractile proteins cause distal arthrogryposis syndromes. Am J Hum Genet. 2003 Mar;72(3):681-90. doi: 10.1086/368294. Citation on PubMed or Free article on PubMed Central