Published on 12, July, 2020
Is it possible that for none autistic parents have an autistic child?
so if parents and grandparents don’t have autism is it possible for the kid to have it? I’m only asking cos there’s a lot of discussion on ahem (Tiktok) highlighting autism is genetic (correct) but what is also being shown is that parents of autistic children are also autistic but in denial and a lot of the family members actually have traits… soo that leads to my question of can a child have autism when no one in the family even has traits of it??
In short, yes. Autism has a large genetic component, but there is an environmental aspect also. Identical twins (share the same genome) exist, where one is autistic and the other is not.
There are also genetic causes, where two non-autistic parents can have an autistic child. First, is genetic sorting, both parents can have autism related alleles (genetic variants), but not at the level to cause autism. But, both a particular sperm and a particular egg can be produced containing all or most of the autism related alleles the parents have. When the gametes combine to create a baby, that baby will have a higher concentration of autism related alleles than either parent had, and might consequently be clinically autistic. Second, is spontaneous mutation. Spontaneous mutation can occur, usually in meiosis during the formation of gametes, where DNA can be deleted, duplicated or transposed (moved) or point mutations can occur (individual DNA letters are changed), if such mutations happen in or near genes important in neurodevelopment or neuronal metabolism an autistic baby can result, neither of the parents being autistic.