Genetic and Molecular Profiling of Neuroligin3, Neuroligin4X and Neuroligin4Y Genes in Autism Spectrum Disorder among the Population of North Karnataka

Abstract

Autism Spectrum Disorder (ASD) or Autism (MIM 209850) is a complex heterogeneous neurodevelopmental disorder. It manifests before the age of three (1). Although autism can be diagnosed at any age, it is described as a “developmental disorder” because symptoms generally appear in the first two years of life. Diagnostic and Statistical Manual of Mental Disorders (DSM-5) is a diagnostic guide created by the American Psychiatric Association that healthcare providers use to diagnose different mental disorders/illnesses. People with ASD often have featured early onset dysfunctions in verbal and non-verbal communication, impairments in social interaction and repetitive and stereotyped behaviours and interests (2). Autism is known as a “spectrum” disorder because there is wide variation in the type and severity of symptoms that individuals experience. Individuals of all genders, races, ethnicities, and economic backgrounds can be diagnosed with ASD. Although ASD can be a lifelong disorder, treatments and services can improve a person’s symptoms and daily functioning. The previous version of the DSM, i.e. the DSM-4, included autism under the umbrella of pervasive developmental disorder and divided autism into five distinct categories ranging from Asperger's syndrome (often used to describe mild or high-functioning autism) to autistic disorder, which indicated severe autism. The 5 diagnostic ranges include autistic disorder, Asperger’s disorder, Pervasive Developmental Disorder Not Otherwise Specified (PDD-NOS), Rett’s disorder and Childhood Disintegrative Disorder (CDD). But the recent version of the DSM, i.e. DSM-V combines all of these into a spectrum of single diagnosis called autism spectrum disorder with different levels of severity (Fig.1) (3).