title: Genetic and orthopedic aspects of collagen disorders.
abstract: OBJECTIVE
  'Collagens' are a family of structurally related proteins that play a wide variety of roles in the extracellular matrix. To date, there are at least 29 known types of collagen. Accordingly, abnormality in the various collagens produces a large category of diseases with heterogeneous symptoms. This review presents genetic and orthopedic aspects of type II, IX, and XI collagen disorders.
  
  
  RESULTS
  Although a diverse group of conditions, mutation of collagens affecting the articular cartilage typically produces an epiphyseal skeletal dysplasia phenotype. Often, the ocular or auditory systems or both are also involved. Treatment of these collagenopathies is symptomatic and individualized. Study of tissue from animal models allows examination of mutation effects on the abnormal protein structure and function.
  
  
  CONCLUSIONS
  The collagen superfamily comprises an important structural protein in mammalian connective tissue. Mutation of collagens produces a wide variety of genetic disorders, and those mutations affecting types II, IX, and XI collagens produce an overlapping spectrum of skeletal dysplasias. Findings range from lethal to mild, depending on the mutation of the collagen gene and its subsequent effect on the structure and/or metabolism of the resultant procollagen and/or collagen protein and its function in the body.
authors.affiliation: Kathryn O. and Alan C. Greenberg Center for Skeletal Dysplasias, Hospital for Special Surgery, New York, New York 11238, USA. csd@hss.edu
authors.forename: Erin M
authors.initials: EM
authors.lastname: Carter
authors.forename: Cathleen L
authors.initials: CL
authors.lastname: Raggio
mesh_terms: D000130:Achondroplasia / Q000175:diagnosis / Q000235:genetics / Q000378:metabolism; D000818:Animals; D002358:Cartilage, Articular / Q000378:metabolism; D003095:Collagen Diseases / Q000175:diagnosis / Q000235:genetics* / Q000378:metabolism / Q000601:surgery; D024043:Collagen Type II / Q000235:genetics / Q000378:metabolism; D024081:Collagen Type IX / Q000235:genetics / Q000378:metabolism; D024161:Collagen Type XI / Q000235:genetics / Q000378:metabolism; D004195:Disease Models, Animal; D005817:Genetic Counseling; D006801:Humans; D007231:Infant, Newborn; D007232:Infant, Newborn, Diseases / Q000175:diagnosis / Q000235:genetics / Q000378:metabolism / Q000601:surgery; D007592:Joint Diseases / Q000175:diagnosis / Q000235:genetics* / Q000378:metabolism / Q000601:surgery; D009154:Mutation
chemical_list: D024043:Collagen Type II; D024081:Collagen Type IX; D024161:Collagen Type XI