Autism in the News

Autism is coming off a big week in the news. The New York Times covered a recent study, which suggested that the risk of autism in children is linked to paternal age since older fathers pass on more mutations to their children. In another New York Times piece, this time an Op-Ed, Moises Velasquez-Manoff offers up the possibility that autism might be an autoimmune disorder. This is an idea with roots in the hygiene hypothesiswhich proposes that conditions like asthma and allergies are the result of a “bored” immune system, no longer burdened with fending off parasites (hence the hygiene), mounting an inappropriate response against the body or otherwise, unharmful, environmental substances (e.g. pollen). Lastly, there was the announcement of an FDA-approved trial using stem cells as a therapy for autism. In a week when headlines were dominated by autism, here were my favorite reads that offered some balance and insight:

On the Paternal Age and Autism linkVirginia Hughes gives us the “Top 3 Reasons to Stop Fretting About Being an Old Dad,” while Seth Mnookin writes about an overlooked implication of this study–”that the genetic health of the species is now facing a serious threat.” With regard to the stem cell trial for autism, Youssef Rizk explores how the design of the trial sidesteps ethical complications by using the patient’s own cord blood stem cell, and Kathleen Raven, rather than simply calling the trial a “cure,” explains the hypothesis being tested in the trial and the, “study’s primary goal…assessing changes in patients’ speaking and understanding of vocabulary.” As for Velaquez Manoff’s Op-Ed piece on autism as an autoimmune disease, Jonathan Eisen laments the “lack of a discussion of the distinction between correlation and causation.” And finally, Emily Willingham, in her critique, isn’t quite buying what Velaquez-Manoff is selling:

“From the headline to the final paragraphs focused on using parasitic worms to treat or even prevent autism, the science as Velasquez-Manoff presents it is limited at best, and frequently unsourced and unreferenced. Where a source is given or traceable, the conclusions are overstated or cherry-picked.”

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3 responses to “Autism in the News

  1. I skimmed the articles about advanced paternal age and I was curious as to whether or not they are factoring in advanced maternal child-bearing age as well? I know there are higher risks as a woman gets older, but do those risks also potentially play a role in the increase of autism? Especially when considering that both men and women seem to be having children later in life (at least in more developed countries where there is more of a career driven society).

    • What the study found was that the rate of mutation increased as a function of paternal age. They could tell the mutation in the child’s DNA was of paternal origin by comparing the child’s DNA sequence with the parent’s DNA. Since some of the mutations occurred in genes that have been reported to play a role in autism the researchers inferred that paternal age might be a risk factor for autism. The logic as to why mutation rates increase as a function of paternal age is that DNA replication in sperm, which is being produced throughout the life of a male, becomes faulty with age–and is therefore prone to mistakes that lead to mutations. Women on the other hand are essentially born with a lifetime supply of eggs. No “faulty” DNA replication is occurring later on in life that might lead to mutations in the DNA contained in eggs. That said, as women age the structural integrity of the DNA, itself, in the eggs may break down causing chromosomal abnormalities, such as deletions of portions of the chromosome.

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