Autism Spectrum Disorder (ASD), also known as Pervasive Developmental Disorders (PDDs), is a learning disability and is a condition characterized by a different learning communication and reaction patterns. It is now estimated to afffect about 3.4 every 1,000 children ages 3-10 in the US. Typically, a definitive ASD diagnosis cannot be made until children are at least 2 years old.

Researchers at Yale School of Medicine, however, report having identified a marker in the placenta that is linked to the incidence of ASD. They say a placental abnormality characterized by the presence of structures called trophoblast inclusions, could potentially help physicians diagnose ASD earlier, possibly even at birth.

They found that the placentas from ASD children were three times more likely to have the inclusions. Kliman and the team identified trophoblast inclusions by performing microscopic examinations of placental tissues.

"We knew that trophoblast inclusions were increased in cases of chromosome abnormalities and genetic diseases, but we had no idea whether they would be significantly increased in cases of ASD," said Kliman. "These results are consistent with studies by others who have shown that ASD has a clear genetic basis."

The results of the study is published in Biological Psychiatry. The researchers now plan to conduct a larger, multi-center prospective studies to confirm their observations.
Read more details from Yale. For more information and stories about autism, check out Dr. Kristina Chew's weblog, AutismVox.

[Photo: A cross-section of the placenta showing an abnormal folding and trophoblast inclusion, from Yale]