Sometimes I think I might know too many useless scientific facts to write a truly interesting science blog. Case in point, I came across a news release today talking about the number of genes in a newly-sequenced, nearly-microscopic crustacean. The headline and attention-grabber was that the animal set a new record for the number of genes in its genome with about 31,000, which is about 8,000 more than humans have in their DNA.
To me, this isn’t news. Only a handful of animals have had their DNA sequenced, and setting new high marks isn’t a big surprise. Nor is setting the mark in such a seemingly simple organism. After all, even an earthworm has more genes than a human.
But I’m guessing not everyone out there knows that.
So here’s a quick overview lesson. The human genome project officially kicked off more than two decades ago in 1990. Scientists believed it would be the Holy Grail to the world of health and medicine. Determining our basic DNA structure would unveil genetic oddities that could be controlled or fixed in order to eliminate things like Parkinson’s disease or even just being short.
But 13 years and 20,000 to 25,000 genes later, researchers discovered just how complex the building blocks of life truly are. Scientists can’t even agree on exactly how many genes there are in the human genome, much less what they all do, partly because most all of them work in a complex web with each other.
Reading headlines about finding the “adventurous gene” or the “depression gene” is mostly crap. There are very few genes that are known to determine one specific trait. For the most part, tens if not hundreds of genes work in tandem to produce the complex people spilling coffee in their laps on a daily basis. Some genes turn on other genes while some modify or even turn off their functions. It’s a crazy jungle in there.
And then there’s something called junk DNA. It seems that a vast majority of our genetic data doesn’t encode proteins or really have much effect on biological functions, though new research on this front is beginning to reveal that it’s not quite junk after all.
Throw in the fact that bits of DNA from viral infections break off and are absorbed from time to time, and finding out that antoher organism – even a much simpler one – has more genes isn’t a surprise.
A modern DNA sequencer can sequence the entire human genome – what originally took 13 years – in a matter of weeks. It’s just a matter of having a good reason to invest the tens of thousands of dollars required to run one of these machines to sequence a new animal.
So while I say kudos to Don Gilbert, coauthor and Department of Biology scientist at Indiana University and the rest of the Daphnia Genomics Consortium, it’s a meaningless mark and one that won’t likely last very long.