[Monogenic obesity: pathophysiology, diagnosis and treatment]

Obesity is a disorder of multifactorial origin in which both genetic and environmental factors intervene. Currently, numerous gene variants related to the control of intake and the mechanism of action of leptin in the central nervous system through the melanocortin pathway have been described. The accessibility to molecular studies through next-generation sequencing panels that include dozens of genes related to this condition shows that the incidence is much higher than previously reported. This review intended to provide information on the diagnostic procedures and therapeutic interventions available specifically for the management of hyperphagia and obesity in affected patients. Early recognition of syndromic and non-syndromic monogenic obesity avoids the indication of risky interventions with no longterm benefit such as surgery and non-specific drugs. The presence of early severe obesity and hyperphagia, together with neurodevelopmental, metabolic and endocrine disorders should lead to the request of genetic studies in search of a definitive diagnosis.