Genetics & Molecular Biology

Researchers have created "Huntington's Disease in a dish" by generating stem cells from skin cells obtained from a person with a severe, early-onset form of Huntington's disease  and turned them into neurons that degenerate just like those affected by the fatal inherited disorder. Although the autosomal dominant gene mutation responsible for HD was identified in 1993, there is no cure. No treatments are available to slow its progression. The general midlife onset and progressive brain damage of HD are especially cruel, slowly causing jerky, twitch-like movements, lack of muscle…

Genetic modification of food has happened for thousands of year.  Tomatoes would still be the size of your thumb without genetic modification. A 2012 study may mean tomatoes of the future could get that much better. They're big business, on the order of 15 million tons of the fruit for processing and fresh-market sales annually, so for decades food scientists in the tomato industry have selected varieties that are uniformly light green before they ripen, in order to produce tomatoes that can be harvested at the same time.  But this characteristic is accompanied by an unintended…

On Sunday there was considerable confusion about the alleged "GMO" grass that killed cattle.  Turns out it was not GMO grass at all, but a hybrid.  I received many inquiries about the difference between a GMO and a hybrid, as the latter sounded truly freaky and much more invasive than any frankenfood. While hybrids are not the technology we usually think of with the terms genetic modification or genetic engineering, it is just that-- humans manipulating plants by modifying the genes of an organism toward crop improvement. No lab needed, just cross two sexually compatible plants…

While the world actually grows enough food to feed all its inhabitants, it isn't equally distributed. Nearly 500 million people in the developing world remain undernourished and, if projections hold true, that number could to 20% within a decade due to the impacts of climate change on global food production, according to a detailed analysis by The Partnership for Maternal, Newborn&Child Health (PMNCH), the World Health Organization (WHO), the UN System Standing Committee on Nutrition (UNSCN), 1,000 Days, World Vision International and partners. According to the analysis, it is…

Last week I wrote about the anti-science campaign being waged by opponents of the use of genetically modified organisms in agriculture. In that post, I promised to address a series of questions/fears about GMOs that seem to underly peoples’ objections to the technology. I’m not going to try to make this a comprehensive reference site about GMOs and the literature on their use and safety. I’m compiling some general resources here, and a list of all FAQs here. Question 1: Isn’t transferring genes from one species to another unnatural and intrinsically dangerous? Question 2)…

Last week I wrote about the anti-science campaign being waged by opponents of the use of genetically modified organisms in agriculture. In that post, I promised to address a series of questions/fears about GMOs that seem to underly peoples’ objections to the technology. I’m not going to try to make this a comprehensive reference site about GMOs and the literature on their use and safety (I’m compiling some good general resources here.) I want to say a few things about myself too. I am a molecular biologist with a background in infectious diseases, cancer genomics, developmental…

In the giant 'Europeans are far more anti-science than Americans' file, we can now add another section on racism. Science can use genetic testing to understand risk factors - some groups have a greater risk than others - but that means interested groups can also do other things with the results.  Europe is terrifically racist, you will never hear a racial slur, much less a stadium-wide chant, at an American sporting event but you are guaranteed to have them at the EURO CUP 2012 tournament. Western Europe is at least trying to drive it out and all those 'end racism' banners are a puzzle…

New chemical compounds that can make key modifications to common sugar molecules - glycans - which are found on the surface of all cells in our body are new tools for investigating treatments for chronic inflammation, autoimmune diseases, cancer metastasis and related conditions. A new study describes compounds that selectively block the attachment to the cell of two types of sugar building blocks, sialic acid and fucose, which are found at the tips of cell surface glycans and can be critical to cell function.  The "glycome", the full set of sugar molecules in living things and even…

Induced pluripotent stem cell (iPSC) research in the last 2 years has faced many twists and turns. With scientists uncovering a number of disturbing genomic abnormalities in these cells, the future of iPSC technology looked like a sea of despair. But lucky for those who persisted in this field of research, recent findings based on deep genome sequencing data revealed that these so-called "genomic abnormalities" simply reflect the normal genomic quirks of the original somatic cells from which iPSCs were derived.  References: Cheng et al, 2012 (Cell Stem Cell 10, 337–344)Young et al 2012…

A major function of microRNAs is to inhibit messenger RNA (mRNA) translation by binding to a specific 3’ untranslated region (UTR) through sequence complementation. In a recent study published in the March 2012 issue of Cell Stem Cell, Boutet et al. discovered that Pax3 transcripts in muscle stem cells in vivo can have both long and short 3’UTRs, an effect controlled by differential poly-adenylation patterns during the course of development. While Pax3 transcripts with long 3’UTRs are susceptible to translational inhibition by miR-206, transcripts with short 3’UTR are profoundly…