Male-limited precocious puberty

Male-limited precocious puberty (MLPP), also known as familial male-limited precocious puberty or testotoxicosis, is a rare genetic disorder characterized by the early onset of puberty in males, typically between the ages of 2 and 5. This condition is caused by mutations in the Luteinizing hormone/choriogonadotropin receptor (LHCGR) gene, which leads to an increased sensitivity of the testes to luteinizing hormone (LH), resulting in the premature production of testosterone.

Symptoms

The primary symptom of MLPP is the early onset of puberty in males. This includes the development of secondary sexual characteristics such as facial hair, deepening of the voice, and increased muscle mass. Other symptoms may include accelerated bone growth, leading to an initially tall stature but ultimately resulting in a shorter adult height due to the early closure of the growth plates in the bones.

Causes

MLPP is caused by mutations in the LHCGR gene. This gene provides instructions for making a protein that is involved in the regulation of testosterone production. Mutations in the LHCGR gene cause the protein to be constantly activated, leading to an increased sensitivity of the testes to LH and the premature production of testosterone.

Diagnosis

Diagnosis of MLPP is based on the observation of early onset puberty in males. This can be confirmed through blood tests showing elevated levels of testosterone. Genetic testing can also be performed to identify mutations in the LHCGR gene.

Treatment

Treatment for MLPP typically involves the use of medications to suppress the production of testosterone. This can help to slow the progression of puberty and prevent the early closure of the growth plates, allowing for a more normal growth pattern.

See also

• Precocious puberty
• Luteinizing hormone
• Testosterone