Abstract
Autism Spectrum Disorder (ASD) is an emerging health problem involving 1 out of every 68 children. The incidence rate of autism has increased 3 folds during the last 3 decades. Due to the illusive picture of aetiology, a considerable number of autistic children fail to receive proper behavioural and medications! treatment. The present study provides a cumulative account of autism risk factors. Several factors including the gene expression and gene mutations, environmental pollution, metal ion accumulation, exposure to pesticides, immune deficiencies, viral infections, mother's age, health, mental status, mother's interactions with the foetus, vaccination of mother and children, and modulations in gut microbiota have been debated. These risk factors may contribute to the development of autism either independently or synergistically leading to a broad spectrum of characteristics observed in autistic patients. The variable quantitative influence of a wide spectrum of risk factors may result in a unique set of features in each autistic individual. However, the exact mechanism behind the combined impact of various aetiological factors is poorly understood hindering the adaptation of specified and effective therapies.