A new study out of the University of California, Davis headed by Jody Van De Water has found that 23% of children with autism spectrum disorders have mothers with a certain combination of antibodies in their blood. Mothers who have this combination are 99% more likely to have autistic children than mothers without the combination. The studies further found that seven proteins active in fetal brains were targeted by the maternal antibodies. The effects of those antibodies were studied and correlated with an autism or autism spectrum diagnosis in a group of 246 children.
In conjunction with this study, another study led by Melissa Bauman (also out of UC, Davis) has found links between maternal antibodies and autism by studying rhesus monkeys and their socialization skills. Rhesus monkeys are known for their complex social structures.
That study looked at the data for three groups: one that was exposed to the maternal autism-linked antibodies, another exposed to antibodies from human mothers whose children were neurotypical, and a third group that did not receive any antibodies. In other words, the study had one test and two control groups.
The study found that rhesus monkey offspring exposed to the autism-linked antibodies showed abnormal social behavior not displayed by the offspring in either of the control groups. This behavior also included approaching unfamiliar monkeys, which is highly unusual for young rhesus monkeys.
While this data represents a huge breakthrough, it's by no means a blanket indicator. This research might lead eventually to specialized screening tests for use before pregnancy, and after birth (to assist in diagnosis), but these antibodies were only found in 23% of the mothers of children on the autism spectrum involved in the study. The vast majority of autism spectrum disorders still seem to develop from a variety of genetic and/or environmental factors.
This is a good piece of a large puzzle, and as always, we just keep trying to put it together.
Read more about the UC Davis studies here.