Results from studies show that ASD affect one in hundred children in UK. ASD affects people from all parts of the world. It affects people of every social economic background and race.
There are many studies looking at the causes of ASD. Although no one specific cause is known, recent studies indicate that ASD may be linked to differences in the brain. In some families, there seems to be a pattern of ASD or related differences in more than one family. This explains the genetics basis of the condition. There is no single gene identified. There are numerous researches looking at the causes of ASD, it appears link with the gene may be just one of three to five or more genes that interact in some way to cause the condition. Scientists suspect that a faulty gene or genes might make a person more likely to develop autism when there are also other factors present, such as a chemical imbalance, viruses or chemicals, or a lack of oxygen at birth. In a few cases, autistic behaviour is caused by: Rubella (German measles) in the pregnant mother, Tuberous sclerosis (a rare genetic disorder that causes benign tumours to grow in the brain as well as in other vital organs), Fragile X syndrome (the most common inherited form of intellectual disability) Encephalitis or meningitis (brain inflammation). However, bad parenting does not cause ASD.