Larsen syndrome

Larsen syndrome (LS), is a rare usually autosomal dominant congenital disorder that occurs in about every 1 in 100,000 people. Its symptoms include hypermobility, congenital dislocations, brachycephaly and cleft palate. It may rarely be recessive.

The condition was first described in a 1950 journal report by L. J. Larsen, et al.

It is caused by a resistance to Growth hormone (GH) secondary to a defect in GH receptors. Investigations reveal high levels of GH and low levels of Insulin like growth factor-1 (IGF-1).

Symptoms
A more complete list of symptoms includes: Resources: www.cleftsmile.org Cleft Lip and Palate Foundation of Smiles
 * Multiple joint dislocations
 * Foot deformities
 * Non-tapering, cylindrical shaped fingers
 * Unusual facial appearance
 * Less commonly occurring:
 * Short stature
 * Additional skeletal abnormalities
 * Cleft palate
 * Heart defects
 * Hearing impairment
 * Mental retardation
 * Pulmonary hypoplasia

Genetics


Larsen syndrome is caused by mutations in the FLNB (Filamin B) gene. The disorder is inherited in an autosomal dominant manner, which means the defective gene responsible for a disorder is located on an autosome, and only one copy of the gene is sufficient to cause the disorder, when inherited from a parent who has the disorder.