SLC6A1 Related Disorder: Clinical Manifestations, Management, and Prognosis

The Solute Carrier family 6 member 1 (SLC6A1) gene found on chromosome 3 is known to regulate gamma-aminobutyric acid (GABA). Variants in this gene tend to occur de novo and rarely in an autosomal dominant fashion. Since its discovery, variants of this gene were initially reported in autistic and epileptic populations. More recently, variants have been associated with comorbid intellectual disability. This syndrome has recently been described as SLC6A1 neurodevelopmental disorder, currently estimated to have a prevalence of 2.65/100,000 births. The manifestations of this disorder range from seizure disorder, varying levels of intellectual disability, psychiatric manifestations, movement, and language disorders. Psychiatric manifestations include neurodevelopmental disorders including autism and attention deficit hyperactivity disorder (ADHD). Other associations include schizophrenia and behavioral issues. Most studies focus on pediatric populations; therefore, the rare prevalence may be underestimated as many adults may not have availed the genetic testing. Despite this, small adult studies have shown consistent features to pediatric populations. Different variants can occur in this gene, which when classified can have diagnostic and therapeutic implications. The need of genetic testing in adults who present with features consistent with this disorder is highlighted as this may guide diagnosis and treatment.