Monogenic Obesity  

What is Monogenic Obesity?

Monogenic obesity is a rare form of obesity caused by mutations in specific genes that affect the regulation of appetite, metabolism, and body weight. Unlike polygenic obesity, which is influenced by multiple genetic and environmental factors, monogenic obesity is linked to one or more specific gene mutations. Conducting a genetic panel for monogenic obesity can provide clear insights into the causes of obesity in individuals who experience unexplained weight gain from a young age, regardless of diet or physical activity.

Genes Involved in Monogenic Obesity

• LEP (Leptin): Controls appetite and metabolism. Mutations in this gene may cause leptin deficiency, resulting in an uncontrollable appetite.
• LEPR (Leptin Receptor): Mutations affect the interaction between leptin and its receptor, disrupting normal appetite regulation.
• MC4R (Melanocortin 4 Receptor): The most common gene associated with monogenic obesity. Mutations in MC4R lead to increased food intake.
• POMC (Pro-Opiomelanocortin): Plays a role in regulating appetite via the hypothalamus.
• PCSK1: Essential for the activation of hormones that regulate hunger and satiety.

How Can Genetic Testing Help?

Genetic testing can identify whether obesity has a genetic basis due to specific mutations. It distinguishes monogenic obesity from other multifactorial forms of obesity. If mutations are detected in children or adolescents, preventive measures can be implemented to curb further weight gain and avoid complications. Understanding the genetic cause can guide targeted treatment, such as administering leptin in cases of deficiency. Additionally, when hereditary mutations are identified, other family members can be evaluated for their risk.