A novel <i>MAOA</i> gene variant: Brunner syndrome, a rare syndrome, is associated with a wide range of psychiatric symptoms

Brunner syndrome is a rare genetic disorder that associated with mutations in the MAOA gene. It has been linked to a number of psychiatric disorders. We present detailed information on psychiatric evaluation of a case carrying a novel MAOA gene variant of p.(Thr408Met). The patient was referred to our clinic with a history of attention problems, motor coordination difficulties and a tendency to bite objects. Following a comprehensive psychiatric evaluation, the patient was diagnosed with developmental coordination disorder, articulation disorder and attention deficit hyperactivity disorder (ADHD). MAOA mutations are rarely reported in the literature. To date, a total of 23 MAOA gene variants, mostly missense variants, have been reported through the HGMD database (Professional 2023.4). Neurodevelopmental symptoms may vary in severity and diversity among patients with Brunner syndrome. Different degrees of intellectual disability have been found in previously reviewed cohorts of Brunner syndrome. In our affected patient, cognitive development and academic achievement were at a similar level to his peers. Additionally, our patient exhibited symptoms suggestive of developmental coordination disorder. Our findings show that genetic mutations in MAOA can lead to a wide range of clinical symptoms and underline the need for comprehensive genetic and clinical evaluations.