Stick with plain old soap

Earlier this month, the Food and Drug Administration (FDA) issued a press release about triclosan  – an ubiquitous antibiotic found in tons of personal care products, including deodorant, toothpaste, hand and facial cleansers, mouthwash, and other household cleaners.  I have long tried to avoid purchasing products like this that were spiked with antibiotics – just on a gut instinct that it can’t be good for our environment to be flushing lots of antibiotics down the drain.  Continue reading

A tasty new molecular sandwich

Many people are vaguely familiar with the basic concepts concerning DNA: it is the genetic material in every one of our cells that make us who we are.  We inherit our DNA from our parents, who in turn inherited it from their parents, etc etc.  Most people also understand the basic structure of DNA: it is a very LONG sequence of nucleotides, referred to as C, G, T, A. If we think of DNA as a necklace, and the C, G, T, and A as beads on this necklace, it is the specific sequence of these C’s, G’s, T’s, and A’s on this necklace that makes us all unique.  This may be where many non-scientists’ understanding of DNA ends.  Continue reading

Autism follow-up: first steps toward a genetic map

Here’s some real science about the cause of autism you can sink your teeth into (as opposed to the rumors and fear-mongering created by the misguided tin-foil hatters who promote the link between vaccines and autism…too harsh?). The Autism-Genome Project just published its second paper about the potential genetics behind autism.  Funded by internation, private, and public partners, the AGP is a consortium of over 50 research centers from Europe, Canada, and the US.  As family studies have demonstrated that autism-spectrum disorder appears to be an inherited trait (ie, one that is genetically passed down through families) the AGP aims to discover the specific genetic factors that cause autism.  The AGP just published an initial paper in the journal Nature titled Functional impact of global rare copy number variation in autism spectrum disorders. The study examined the genomes (the entirety of an organism’s hereditary information) of 996 individuals diagnosed with autism as well as a control group of 1,287 individuals who are not autistic.  They found that overall, autistic individuals were more likely to have a higher number of copy number variations within their genomes than the non-autistic individuals.  Copy number variations exist throughout the human genome, and are simply a stretch of the DNA that has been duplicated once or multiple times.  Some of these genetic variants pointed to genes previously implicated in autism or other related intellectual disabilities.  However, many of these genetic variants were found in networks of genes involved in more basic cellular functions, such as cellular proliferation (cell growth and division).

Interestingly, although autistic individuals did have a higher number of copy number variations than the control group, each of the copy number variations found were quite rare.  Unfortunately we can’t point a finger now at a specific gene, or even a specific gene family/network, as a single cause of autism.  This seems to make sense, as autism is really a spectrum of different disabilities with differing levels of severity.  If there is so much variability in the symptoms of autism, we could expect there would be an equal amount of variability in the underlying genetic basis for this disease.  So, while this new research is important from a genetics and scientific point-of-view, the potential applications of this information are off in the distant future.

The vaccine-autism link: bad information for scared parents

Two articles published in the New York Times caught my interest this month (3 Rulings Find No Link to Vaccines
and Autism
and Court Says Vaccine Not to Blame for Autism).  The articles described the dismissal of court cases where parents were suing vaccine manufacturers for giving their children autism.  Some parents claimed that a preservative containing mercury, Thimersol, caused autism. Others claimed that the Measles, Mumps, and Rubella (MMR) vaccine can contribute to causing either autism or gastrointestinal dysfunction (and gastrointenstinal dysnfunction has links to autism).  This made me curious – where did the whole MMR-causes-autism hypothesis come from?  What science is there on either sides of this debate?  And where does the science stand now? If you just want the summary, here you go: there is no conclusive evidence that MMR causes autism.  There is lots of evidence that it in fact DOES NOT cause autism.  Read on for more information on some of the original science to arm yourself against the shucksters who perpetrate this myth to prey on desperate parents.  While this is not an exhaustive review of every paper published on this topic, I tried to pick representative papers and looked at only those articles published in peer-reviewed journals (a basic and important standard for scientific research). Continue reading

A sticky question – explained

As ‘A Sticky Question’ was my first blog post as a science blogger.  I emailed the post to family and friends and asked for their honest assessments.  I think the biggest thing people were looking for (especially from my non science-y contacts) was a more concise summary of my findings.  While as a chemist I found it really informative to learn about the structures and makeup of different sugars and sweeteners, those without science backgrounds seemed to get a little bogged down in the background information.

To evaluate the different claims about the relative dangers of high fructose corn syrup vs table sugar, I went to the HFCS Wikipedia article.  Now, I know very well that Wikipedia is really not the best source for scientific information.  The Wikipedia section on the health effects of HFCS is ‘under dispute’ so rather than reading the Wikipedia article, I went to the original scientific research articles the Wikipedia article cited.  It is the various interpretations of these Wikipedia articles that has led to such a vigorous debate about HFCS.  There were four main articles that seemed to be at the center of the debate, so I analyzed those articles myself. Continue reading