Diseases & Conditions


A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Dyggve Melchior Clausen Syndrome


Synonyms of Dyggve Melchior Clausen Syndrome
  • DMC disease
  • Pseudo-Morquio disease type I
  • Smith-McCort dysplasia
  • Smith-McCort syndrome

Disorder Subdivisions

  • Smith-McCort dysplasia


General Discussion
Dyggve-Melchior-Clausen (DMC) syndrome is a rare, progressive genetic disorder characterized by abnormal skeletal development, microcephaly and mental retardation. Skeletal abnormalities may include a barrel-shaped chest with a short truck, partial dislocation of the hips, genu valgum (knocked knees) or varum (bowed legs), and decreased joint mobility. In 11% of patients, there is atlantoaxial (upper neck vertebrae) instability that can lead to spinal cord compression, weakness and paralysis. Normally, there is growth deficiency resulting in short stature. Radiographic findings in older children and adults are pathognomonic for the disorder. The condition, DMC results from mutations in the DYM (dymeclin) gene and is inherited in an autosomal recessive mode. A variant of DMC syndrome, Smith-McCort syndrome (SMS), has identical skeletal abnormalities, but lacks the mental deficiency. SMS is also caused by mutations in DYM, and thus is allelic to DMC. Both are classified as osteochondrodysplasias, specifically a spondyloepimetaphyseal dysplasia; this latter category consists of 27 separate disorders.

Organizations related to Dyggve Melchior Clausen Syndrome
  • Human Growth Foundation
    997 Glen Cove Avenue
    Glen Head NY 11545
    Phone #: 516-671-4041
    800 #: 800-451-6434
    e-mail: hgf1@hgfound.org
    Home page: http://www.hgfound.org/
  • Little People of America, Inc.
    250 El Camino Real
    Tustin CA 92780
    Phone #: 714-368-3689
    800 #: 888-572-2001
    e-mail: info@lpaonline.org
    Home page: http://www.lpaonline.org
  • MAGIC Foundation for Children's Growth
    6645 W. North Avenue
    Oak Park IL 60302
    Phone #: 708-383-0808
    800 #: 800-362-4423
    e-mail: mary@magicfoundation.org
    Home page: http://www.magicfoundation.org
  • March of Dimes Birth Defects Foundation
    1275 Mamaroneck Avenue
    White Plains NY 10605
    Phone #: 914-428-7100
    800 #: 888-663-4637
    e-mail: Askus@marchofdimes.com
    Home page: http://www.marchofdimes.com
  • NIH/National Institute of Child Health & Human Development (Preg & Perinat)
    Pregnancy and Perinatology Branch
    Bethesda MD 20892-7510
    Phone #: 301-496-5575
    800 #: --
    e-mail: BOCKR@mail.nih.gov
    Home page: http://www.nichd.nih.gov
  • The Arc (a national organization on mental retardation)
    1010 Wayne Ave
    Silver Spring MD 20910
    Phone #: 301-565-3842
    800 #: 800-433-5255
    e-mail: info@thearc.org
    Home page: http://www.thearc.org/



For a Complete Report

This is an abstract of a report from the National Organization for Rare Disorders, Inc. ? (NORD). A copy of the complete report can be obtained for a small fee by visiting the NORD website. The complete report contains additional information including symptoms, causes, affected population, related disorders, standard and investigational treatments (if available), and references from medical literature. For a full-text version of this topic, see http://www.rarediseases.org/search/rdblist.html