Breakthrough In Human Genetics

Many readers have submitted this story about a breakthrough in our understanding of human DNA: in particular, how much variation can exist between peoples' genes and how genes are involved with certain diseases. "One person's DNA code can be as much as 10 percent different from another's, researchers said on Wednesday in a finding that questions the idea that everyone on Earth is 99.9 percent identical genetically. They said their new version of the human genetic map, or 'book of life,' fills in many missing pages and chapters to explain how genes are involved in common diseases. The Human Genome Project mapped the billions of letters that make up the human genetic code. Scientists later refined the map by looking for single variations called SNPs or single nucleotide polymorphisms. The CNV map gives researchers a different way to look for genes linked to diseases by identifying gains, losses, and alterations in the genome."

Comments

Re:Spelling on Slashdot

[Almost-Retired]

Humm, do I detect a faint case of the pot calling the kettle black here?

Seriously, far more of my spelling mistakes are uncorrected typo's and until I got the touchpad on this lappy turned off tonight, from miss-fires of that POS.

To get back on topic, I think as their mapping techniques improve, they are going to find a hell of a lot more than todays quoted 12-15% differences. Many of those will be indicators of a disease, or a precursor marker for one. However, it still scares me that there will inevitably be those who would take upon themselves to improve on man by selectively erasing those genes known to be deleterious. Thats playing God, and God has had many tens of millions of years to both record history in these genes and to figure out what works over time scales these Johnny come lately's cannot begin to appreciate. For instance, fixing the sickle-cell problem in blacks: That gives an immunity to malaria that I as a caucasian don't have, and its entirely possible that if the sickle-cell problem was fixed, and 300 years elapsed so that the majority of the blacks were of the fixed lineage, then along comes a new variety of malaria, wipeing out 99% of them in one swell foop.

Lets not allow them to go down that slippery slope, I do not see it as being good for "man" over geological time spans. And I hope that we do not invent something that winds up sterilizing this puny little planet, but there are those who would gleefully do it. And we *think* we know who they are. But as Pogo said, we have met the enemy, and he IS us...

--
Cheers, Gene

Re:Natural Selection no longer applies to humans

[Miraba]

I don't buy that myopia is a result of environment.

Perhaps "upbringing" is the wrong word, but it's certainly not limited to genetics. The Wikipedia article calls it "school myopia". See the "Theories" section as well.

I'll buy diabesity (diabetes + obesity) being related to upbringing, but I really think we're starting to have a genetic disposition towards obese people, which obese genes would probably have been culled.

Such a "disposition" (and you do realize that the word should not be used when talking about populations of individuals) has mainly occurred in the fairly recent past, such as the past two or three generations.

Asthma is probably the biggest one that's a result of upbringing, and I'll bet there's still a genetic component.

Please read the WP sections on epidemiology and pathogenesis. There are certainly genetic factors, but to suggest that asthma (and allergies in general) wouldn't be a problem if the genes were "culled" is uninformed.

Humans have no natural predators, so we have no one to cull the herd for us.

Bzuh? We certainly used to have (animal) predators, and we still do in certain parts of the world. Diseases can be considered predators (and rather good ones, too). The weather is quite capable of killing us as well. Also, see physical injury and/or death inflicted by other humans.

The external pressures are not as important as they used to be, but that's not to say they don't (or didn't ever) exist.

This, combined with the "every life is precious" view, means that the only solution is to prevent the conception of individuals who would have been culled if not for the marvels of modern society, which I suggest doing by screening for genetic defects before doing in vitro fertilization.

I'm not exactly sure what you're getting at, but I have no problem with screening for genetic defects.

Otherwise, we will reach a point where the health care system implodes trying to accommodate the poor genetic code that remains.

Please read about Hardy-Weinberg genetics. If genetic defects have no bearing on one's ability to reproduce (as you say) and who one reproduces with, then it's the same as any other gene and the percentage will remain stable in a population. It will not increase.

As far as having an impact on whether someone can reproduce, the only things I'm aware of are low fertility or sterility. Even someone like Rain Man could impregnate someone these days.

There are behavioral barriers (being too shy to ever get a date and dying a virgin), societal barriers (taboos), and physical barriers (facial disfigurement is hard to ignore).

I see that you're a hardware engineer. I'm a biologist. How about I don't lecture you on physics and you don't lecture me on population genetics?