A new discovery raises hope that autism（孤独症，自闭症） may be more easily diagnosed and that its effects may be more reversible（可逆的，可撤销的） than previously1 thought. In a new study appearing online in The FASEB Journal (http://www.fasebj.org), scientists have identified a way to detect the disorder2 using blood and have discovered that drugs which affect the methylation（甲基化） state ("DNA3 tagging") of genes4 could reverse autism's effects. This type of drug is already being used in some cancer treatments. "As the mother of a now 22-year-old son with an autism spectrum5（光谱，频谱） disorder, I hope that our studies as well as those of others, will lead to therapies that are designed to address specific deficiencies（缺陷，不足） that are caused by autism, thus improving the lives of affected6 individuals," said Valerie W. Hu, Ph.D., one of the researchers involved in the work from the Department of Biochemistry and Molecular7 Biology at The George Washington University Medical Center in Washington, D.C. "Since autism is very diverse in the array of symptoms present in any given individual, it is first necessary to be able to identify specific deficits8 in each individual in order to design and then prescribe the best treatment. As an example of this personalized approach to medicine, we identified RORA as one of the genes that was altered specifically in the sub group of autistic individuals who exhibited severe language deficits."
To make their discovery, Hu and colleagues identified chemical changes in DNA taken from cells of identical twins and sibling（同辈，兄弟姐妹） pairs, in which only one of the twins or siblings9 was diagnosed with autism. The researchers then compared genes that showed changes in DNA tagging (methylation) with a list of genes that showed different levels of expression from these same individuals. Then the scientists studied the amount of protein product produced by two genes that appear on both lists in autistic and control regions of the cerebellum（小脑） and frontal cortex（前额叶） of the brain. They found that both proteins, as predicted by the observed increase in DNA tagging, were reduced in the autistic brain. This suggests that blocking the chemical tagging of these genes may reverse symptoms of the disorder and demonstrates the feasibility（可行性，可能性） of using more easily accessible cells from blood (or other non-brain tissues) for diagnostic screening.
"For far too long, autism research has been side-tracked by the cranky（暴躁的，古怪的） notion that it's caused by the MMR vaccine," said Gerald Weissmann, M.D., Editor-in-Chief of The FASEB Journal. "Studies like this, which define genetic10 and epigenetic（外成的，后生的） changes in discrete11 subgroups of the autism spectrum, offer real hope that effective treatments and accurate diagnosis12 are closer at hand."
收听单词发音 
