Welcome to the December 2006 edition of Mendel’s Garden, a blog carnival dedicated to genetics. Shake the snow off your boots, sit down by the crackling fire, and warm up with a beverage hot off the thermocycler. Together we’ll investigate how genes might affect our lives this holiday season…
We’re tempted to gorge on gingerbread and eggnog, but is eating too much going to kill us? After all, lab mice on low-calorie diets live longer than those who eat their fill. Over at Ouroboros, Chris Patil shows us some new research that offers hope for our hungry bellies: the lifespan of wild mice is unaffected by how much they eat. The phenomenon in lab mice could be a weird artifact of domestication, and we might be more like wild mice. If so, maybe it doesn’t matter how much we eat… or maybe it depends on our genes.
Visits from family and friends during the holidays are wonderful, but they can wear you out. Apparently the same thing happens to fruit flies. Coturnix at A Blog Around the Clock reports on a study showing that social interaction makes flies sleep more. Knocking out genes related to the senses and memory reduces this effect, suggesting that it’s the flies’ perception of other flies around them that makes them feel sleepy. So if the relatives are making you exhausted, just close your eyes and pretend they aren’t there.
You’re going to want to watch some movies while relaxing on your winter break, and here’s one that’s fun for the whole family: GrrlScientist at Living the Scientific Life presents an awesome video of a molecular dance called RNAi. Through computer technology, our ability to demonstrate subcellular processes has come a long way since the days when they had to use live hippies (warning: large file).
I have often wondered whether volant reindeer constitute an evolutionary lineage that is distinct from other cervids, or if the gene for flight is just segregating in certain populations of caribou. Jeremy at The Voltage Gate considers the whole concept of “subspecies,” and whether it’s a useful way of classifying genetic variation below the species level.
Everyone loves presents, and you might still have to go shopping for all those people on your list. Hsien-Hsien Lei at Genetics and Health has amassed a catalog of DNA-themed gifts you can purchase for your loved ones. I especially like the DNA cartoons. Why must you never say “oops!” in a “DNA lab?” I guess the implication is that we’re constantly one tiny mistake away from accidentally unleashing a genetically modified monster on the world. I’ll try to be careful next time I do PCR.
Exchanging gifts is not thought to cause mutations. But what about exchanging chromosomal regions? Within the genome, polymorphism (variation) is correlated with the recombination rate (how often chromosomes swap genes). This pattern has long been attributed to natural selection. But could recombination-induced mutations be the explanation? RPM at Evolgen discusses how the answer might depend on whether you’re a human or a fly.
Once you’ve given your gifts, you can turn your attention to the more important business of getting your own gifts out of their wrapping paper and into your hands. Alex at The Daily Transcript explains how cells have more than one way of getting their mRNA out of their nuclear wrapper and into the cytoplasm. Thus, gene expression could potentially be regulated at this stage between transcription and translation.
Finally, the best thing you can do this holiday season is work towards that dream of “peace on Earth, goodwill to all.” I recently posted on how our species is even more genetically diverse than it may appear, due to variation in the number of copies of DNA segments. Let us extend our brotherly and sisterly love to people with genomes of all shapes and sizes.
Thus we conclude this month’s edition of Mendel’s Garden. You can visit Neurotopia in January for the next installment. If you’ve written a blog post about genetics, submit it to the next Mendel’s Garden using the carnival submision form. From all of us at Salamander Candy, we wish you a Merry Fitness and HapMap New Year.