Your browser does not support javascript:   Search for gard hereSearch for news-and-events here.


Genetic and Rare Diseases Information Center (GARD)

Print friendly version

Congenital muscular dystrophy type 1A

Other Names for this Disease
  • LAMA2-related muscular dystrophy
  • Laminin alpha-2 deficiency
  • MDC1A
  • Merosin-deficient congenital muscular dystrophy
  • Merosin-negative congenital muscular dystrophy
More Names
See Disclaimer regarding information on this site. Some links on this page may take you to organizations outside of the National Institutes of Health.


Newline Maker

What are the signs and symptoms of congenital muscular dystrophy type 1A?

Infants with congenital muscular dystrophy type 1A (MDC1A) typically have poor muscle tone (hypotonia) and muscle weakness at birth. Within weeks after birth, some affected infants may have feeding and respiratory difficulties. Motor development is often delayed and limited. Most affected infants can sit unsupported and some can stand without assistance. Only a few children with MDC1A are eventually able to walk unassisted.[1] Additional signs and symptoms that affected individuals may experience include joint contractures (stiff or "frozen" joints), congenital hip dislocation, scoliosis, and ophthalmoplegia (paralysis or weakness in the muscles of the eye).[1] Affected children may also develop an elongated face. Approximately 20-30% experience seizures.[2] The majority of affected individuals have normal intellectual abilities.[2] The prognosis of this condition is poor, as many affected children do not reach adolescence.[3]

Although most individuals affected with MDC1A have complete deficiency of the merosin protein, a few individuals have only a partial deficiency. Among individuals with a partial deficiency, the severity and age of onset varies greatly.[2] One study reported that approximately 12% of individuals have later onset, slowly progressive weakness.[4]
Last updated: 9/26/2011

  1. Congenital Muscular Dystrophy. NORD. January 6, 2010; Accessed 9/26/2011.
  2. Susan Sparks et al. Congenital Muscular Dystrophy Overview. GeneReviews. January 4, 2011; Accessed 9/26/2011.
  3. M. Fardeau. Congenital muscular dystrophy type 1A. Orphanet. April 2009; Accessed 9/26/2011.
  4. K. Jones et al. The expanding phenotype of laminin a2 chain (merosin) abnormalities: case series and review. J Med Genet. October 2001; 38(10):649-657.