Information on Laron Syndrome

Laron syndrome type I (LTD1) a rare genetic disorder. Laron syndrome is caused by the body's inability to use the growth hormone (GH) that it produces. Laron syndrome type I (LTD1) causes short stature. People with this disease lack certain receptors that are important to human growth. Laron Syndrome is normally developed shortly after birth.  Laron Syndrome occurs more often in girls than boys.  Also, people with the disease usually have deep-set eyes, smaller hands and feet, and a high pitched voice.

Consanguinity has been a main contributor to its expansion in described populations.  The diversity of mutations in the GHR gene that cause LS is quite striking. The more than 33 mutations reported to date range from exon deletions to a variety of point mutations, including missense, nonsense, splice, and frame shift mutations. Considering that the underlying GHR mutation has been described in only half of the known cases of LS, additional mutations likely exist. Most defects are in the extra cellular hormone-binding domain, resulting in absence of circulating GHBP.

Symptoms of Laron syndrome involve prominent forehead, depressed nasal bridge, under-development of mandible, truncal obesity and a very small penis. Seizures are frequently secondary to hypoglycemia. Several genetic variations have an force upon intellectual capacity. Treatment of Laron syndrome with human growth hormone is ineffective because people with the disease lack the receptors they need to use the growth hormone. Periodic blood sugar monitoring is necessary for some patients with LS and for all patients with LS who are receiving rhIGF-I therapy.