The genome analysis of 2,064 people revealed a number of autologous genetic abnormalities. The study suggests that the sequencing of the entire genome could one day contribute to the diagnosis.
It is now certain that autism has genetic bases. The current tests, however, are not always able to identify the anomalies that are the cause. The study identified new genetic patterns that could help in the absence of other genetic markers. If they were confirmed, they could become a guide to early diagnosis of the disorder.
The complete sequencing of the human genome is becoming easier and cheaper. So much so that, according to the author of the study Evan Eichler, within 10 years it could become the best diagnostic tool for autism.
Current genetic tests focus only on genome areas already linked to autism. Other tests are looking for anomalies in well-defined genes. However, based on family histories, inheritance plays a decisive role only in 50% of cases. Consequently, the approach covers only 10-30% of cases.
The researchers sequenced the genome of 516 autistic children. Children did not have family history autism stories and none of the abnormalities normally detected by the tests. Scientists also sequenced the genome of parents and children's brothers, for a total of 2,064 people.
The team identified abnormalities that have destroyed some genetic functions and altered protein production. They also found modifications in areas of the genome without genes but responsible for the activation of some important genes.
Comparing the number of genetic variations in autistic children and brothers, it was found that the former had often three or more types of anomalies. This suggests that the combination of several sporadic variations could contribute to autism. However, further studies will be needed.