<< July 2014 >>
Sun Mon Tue Wed Thu Fri Sat
 01 02 03 04 05
06 07 08 09 10 11 12
13 14 15 16 17 18 19
20 21 22 23 24 25 26
27 28 29 30 31


If you want to be updated on this weblog Enter your email here:



rss feed



Jul 6, 2014
The blood becomes too thick and raises our blood pressure.

He told BBC News: "If you and I go up to high altitude, we'll immediately have various negative physiological pola ba effects. We'll be out of breath, we might suffer from altitude sickness.

"After a little while, we'll try to compensate for this by producing more red blood cells. But because we're not adapted to the high altitude environment, our response would be maladaptive - we would produce too many red blood cells.

"The blood becomes too thick and raises our blood pressure, placing us at risk of stroke and pre-eclampsia (in pregnant women)."

But Tibetans pola ba are protected against these risks by producing fewer red blood cells at high altitude. This keeps their blood from thickening.

The Tibetan variant of EPAS1 was discovered by Prof Nielsen's team in 2010. But the researchers couldn't explain why it was so different from the DNA sequences found in all other humans today, so they looked to more ancient genome sequences for an answer.

"We compared it to Neanderthals, but we couldn't find a match. Then we compared it to Denisovans pola ba and to our surprise there was an almost exact match," he explained.

He says the interbreeding event with Denisovans probably happened very long ago.


Posted at 08:20 pm by huhweu

 

Leave a Comment:

Name


Homepage (optional)


Comments




Previous Entry Home Next Entry