Is Genetics Implicated in the Causation of Autism?
Samashaptak1, Pratnoja Das1, Sukanti Bhattacharyya2* and Tarun Kumar Datta3
1Undergraduate Medical Student (MBBS), ICARE Institute of Medical Sciences and Research and Dr. Bidhan Chandra Roy Hospital, Haldia, West Bengal, India
2Associate Professor, Department of Medical Physiology, ICARE Institute of Medical Sciences and Research and Dr. Bidhan Chandra Roy Hospital, Haldia, West Bengal, India
3Clinical Psychologist, Pavlov Research Institute and Hospital, Kolkata, West Bengal, India
*Corresponding Author: Sukanti Bhattacharyya, Associate Professor, Department of Medical Physiology, ICARE Institute of Medical Sciences and Research and Dr. Bidhan Chandra Roy Hospital, Haldia, West Bengal, India.
December 31, 2021; Published: February 14, 2022
Autism is a neurodevelopmental disorder first introduced by Kanner in 1943. Presently, a group of disorders collectively is considered to be ‘Autism Spectrum Disorder’ which is an outcome of complex interaction between genes and the environment.
In this investigation, authors considered the historical development of genetic study that revealed the secret of genes responsible for autism. They noted that synapse-related risk genes and susceptibility genes affecting transcription and chromatin-remodelling pathways have an important role behind the mechanism of the disease.
But there are environmental factors also. Currently 40%-80% of autism cases are related to some risk genes, but epigenetic, particularly environmental modifiers, like advanced age of father, gestational complications and infections, prenatal exposure to anti-convulsants, or paucity of oestrogen in developmental brain are also playing fundamental roles in heterogeneity of manifestations.
Till date, hundreds of genes have been recognized along with the environmental factors but how they interact to manifest the disease is still unknown due to complexities in interaction and overlap between different neuro-psychiatric disorders.
Presence of second level modifiers has made the situation more multifaceted. However, advancements in sequencing technology, analyzing software, and expansion of databases have made the study of genetic modifiers possible.
Going through the works by various scientists across the globe over the last 75 years, authors have identified a number of chromosomes, multitudes of gene loci, many genetic overlaps, and myriads of modifiers - endocrinal, environmental, and epigenetic. But, at the same time they have warned that though genes play a pivotal role, the other factors also need to be considered and studied in detail with proper attention and finally synthesis all the information reasonably to discover the root cause of autism.
Keywords: Autism; ASD; Neurodevelopmental Disorders; Neuro-psychiatric Disorders; Genetics; Epigenetics
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