SNP Shot: Genomic Insights

Laron syndrome is a rare condition causing short stature. It occurs because the body cannot properly use growth hormone, which is normally produced by the pituitary gland and essential for growth. Babies with Laron syndrome are generally of normal size at birth, but their growth slows considerably in early childhood, leading to significant short stature. Without treatment, adult males typically reach a maximum height of about 4 feet 6 inches, and adult females may only grow to just over 4 feet.

Untreated Laron syndrome can also involve other characteristics, such as decreased muscle strength and stamina, episodes of low blood sugar (hypoglycemia) in infancy, small genitalia and delayed puberty, thin and brittle hair, and dental problems. Many individuals with this condition have recognizable facial features, including a prominent forehead, a depressed nasal bridge (saddle nose), and a bluish tinge to the whites of the eyes (blue sclerae). They tend to have shorter limbs relative to their torso size, along with small hands and feet. Obesity commonly develops in adults with Laron syndrome. It's important to note that the signs and symptoms can vary among individuals, even within the same family.

Research indicates that people with Laron syndrome have a substantially lower risk of developing cancer and type 2 diabetes. They seem to develop these diseases much less often than their relatives who do not have the syndrome, even though they frequently experience obesity (which is normally a risk factor for both cancer and type 2 diabetes). However, their lifespan does not appear to be increased compared to their relatives without Laron syndrome.

Inheritance:

In most instances, Laron syndrome is inherited in an autosomal recessive manner. This means that both copies of the GHR gene in each cell must have mutations for the condition to develop. The parents of a child with an autosomal recessive condition each carry one copy of the mutated gene but usually do not exhibit any symptoms of the condition themselves. In rarer cases, the condition follows an autosomal dominant inheritance pattern. This means only one copy of the altered gene in each cell is enough to cause the disorder. Typically, in these cases, an affected individual has one parent who also has the condition.