Authors' recommendations: Ehlers-Danlos syndrome (EDS) is a group of heritable connective tissue disorders that is typically divided into 6 major subtypes. The classic type of EDS (which includes earlier classifications of EDS types I and II) is estimated to occur in 1 in 20,000 individuals and is characterized by significant joint laxity, hyperelastic skin, and atrophic scars resulting from tissue fragility. Individuals with classic EDS are likely to experience recurrent joint dislocations, musculoskeletal abnormalities (such as flat feet and spinal curvatures), and easy bruising. Additional features include the presence of molluscoid pseudotumors (fleshy lesions associated with scars) and subcutaneous spheroids (small, hard, spherical bodies under the skin that are frequently palpable and mobile). They also have an increased risk for delays in gross motor development, hernias, rectal prolapse, cervical insufficiency, and premature rupture of the amniotic membranes during pregnancy. Vascular complications are not considered common among individuals with classic EDS, but mitral valve prolapse, aortic dilatation, and arterial rupture have been reported in affected individuals. Classic EDS is usually diagnosed using the Villefranche classification system, which includes both major and minor criteria for the clinical diagnosis of the various types of EDS. The combination of three major criteria (hyperextensible joints, hyperelastic skin, and atrophic scars) is considered highly specific for classic EDS, while additional minor criteria contribute to the diagnosis of this clinical subtype. Medical management for patients with classic EDS involves adaptations in lifestyle to minimize the risk of wounds and injuries, and treatment of complications. Classic EDS, which is inherited in an autosomal dominant manner (i.e., only 1 pathogenic variant in the causative gene is necessary to have the condition), may be caused by a variant in 1 of 2 collagen type V genes: COL5A1 (located on chromosome 9 at band q34.3) or COL5A2 (located on chromosome 2 at band q32.2). The COL5A1 and COL5A2 genes encode the alpha ()1 and 2 chains of collagen type V, respectively. Pathogenic variants in these genes may lead to either a decreased amount of functional collagen type V (i.e., haploinsufficiency) or the production of an abnormal alpha chain that interferes with the function of normal collagen proteins (i.e., a dominant negative effect). Currently, it is estimated that 50% of patients with a clinical diagnosis of classic EDS have a detectable variant in either COL5A1 or COL5A2, with most of these in COL5A1. Of patients with a detectable COL5A1 or COL5A2 gene variant, approximately half have inherited the diseasecausing variant from an affected parent and half have the condition as a result of a de novo sequence variant.

Project Status: Completed

Year Published: 2013

URL for published report: The report may be purchased from:http://www.hayesinc.com/hayes/crd/?crd=14849

English language abstract: An English language summary is available

Publication Type: Not Assigned

Country: United States

Organisation Name: HAYES, Inc.

Contact Address: 157 S. Broad Street, Suite 200, Lansdale, PA 19446, USA. Tel: 215 855 0615; Fax: 215 855 5218

Contact Name: saleinfo@hayesinc.com

Contact Email: saleinfo@hayesinc.com

Copyright: <p>HAYES, Inc.</p>