Featured Research

from universities, journals, and other organizations

Obesity and diabetes are a downside of human evolution, research suggests

Date:
February 25, 2011
Source:
Federation of American Societies for Experimental Biology
Summary:
As if the recent prediction that half of Americans will have diabetes or pre-diabetes by the year 2020 isn't alarming, a new genetic discovery provides a disturbing explanation as to why: we took an evolutionary "wrong turn." In the report, scientists show that human evolution leading to the loss of function in a gene called "CMAH" may make humans more prone to obesity and diabetes than other mammals.

As if the recent prediction that half of all Americans will have diabetes or pre-diabetes by the year 2020 isn't alarming enough, a new genetic discovery published online in the FASEB Journal provides a disturbing explanation as to why: we took an evolutionary "wrong turn." In the research report, scientists show that human evolution leading to the loss of function in a gene called "CMAH" may make humans more prone to obesity and diabetes than other mammals.

Related Articles


"Diabetes is estimated to affect over 25 million individuals in the U.S., and 285 million people worldwide," said Jane J. Kim, M.D., a researcher involved in the work from the Department of Pediatrics at the University of California, San Diego in La Jolla, CA. "Our study for the first time links human-specific sialic acid changes to insulin and glucose metabolism and therefore opens up a new perspective in understanding the causes of diabetes."

In this study, which is the first to examine the effect of a human-specific CMAH genetic mutation in obesity-related metabolism and diabetes, Kim and colleagues show that the loss of CMAH's function contributes to the failure of the insulin-producing pancreatic beta cells in overweight humans, which is known to be a key factor in the development of type 2 diabetes. This gene encodes for an enzyme present in all mammalian species except for humans and adds a single oxygen atom to sialic acids, which are sugars that coat the cell surface.

To make their discovery, the researchers used two groups of mice. The first group had the same mutant CMAH gene found in humans. These mice demonstrated that the CMAH enzyme was inactive and could not produce a sialic acid type called NeuSGc at the cell surface. The second group had a normal CMAH gene. When exposed to a high fat diet, both sets of mice developed insulin resistance as a result of their obesity. Pancreatic beta cell failure, however, occurred only in the CMAH mutant mice that lacked NeuSGc, resulting in a decreased insulin production, which then further impaired blood glucose level control. This discovery may enhance scientific understanding of why humans may be particularly prone to develop type 2 diabetes. Results may also suggest that conventional animal models may not accurately mirror the human situation.

"The diabetes discovery is an important advance in its own right. It tells us a lot about what goes wrong in diabetes, and where to aim with new treatments," said Gerald Weissmann, M.D., Editor-in-Chief of the FASEB Journal, "but its implications for human evolution are even greater. If this enzyme is unique to humans, it must also have given us a survival advantage over earlier species. Now the challenge is to find the function of CMAH in defending us against microbes or environmental stress or both. This evolutionary science explains how we can win some and lose some, to keep our species ahead of the extinction curve."


Story Source:

The above story is based on materials provided by Federation of American Societies for Experimental Biology. Note: Materials may be edited for content and length.


Journal Reference:

  1. Sarah Kavaler, Hidetaka Morinaga, Alice Jih, WuQiang Fan, Maria Hedlund, Ajit Varki, and Jane J. Kim. Pancreatic β-cell failure in obese mice with human-like CMP-Neu5Ac hydroxylase deficiency. FASEB J., fj.10-175281 DOI: 10.1096/fj.10-175281

Cite This Page:

Federation of American Societies for Experimental Biology. "Obesity and diabetes are a downside of human evolution, research suggests." ScienceDaily. ScienceDaily, 25 February 2011. <www.sciencedaily.com/releases/2011/02/110224145647.htm>.
Federation of American Societies for Experimental Biology. (2011, February 25). Obesity and diabetes are a downside of human evolution, research suggests. ScienceDaily. Retrieved March 29, 2015 from www.sciencedaily.com/releases/2011/02/110224145647.htm
Federation of American Societies for Experimental Biology. "Obesity and diabetes are a downside of human evolution, research suggests." ScienceDaily. www.sciencedaily.com/releases/2011/02/110224145647.htm (accessed March 29, 2015).

Share This


More From ScienceDaily



More Health & Medicine News

Sunday, March 29, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

S. Leone in New Anti-Ebola Lockdown

S. Leone in New Anti-Ebola Lockdown

AFP (Mar. 28, 2015) Sierra Leone imposed a three-day nationwide lockdown Friday for the second time in six months in a bid to prevent a resurgence of the deadly Ebola virus. Duration: 01:17 Video provided by AFP
Powered by NewsLook.com
These Popular Antibiotics Can Cause Permanent Nerve Damage

These Popular Antibiotics Can Cause Permanent Nerve Damage

Newsy (Mar. 27, 2015) A popular class of antibiotic can leave patients in severe pain and even result in permanent nerve damage. Video provided by Newsy
Powered by NewsLook.com
WH Plan to Fight Antibiotic-Resistant Germs

WH Plan to Fight Antibiotic-Resistant Germs

AP (Mar. 27, 2015) The White House on Friday announced a five-year plan to fight the threat posed by antibiotic-resistant bacteria amid fears that once-treatable germs could become deadly. (March 27) Video provided by AP
Powered by NewsLook.com
House Ready to Pass Medicare Doc Bill

House Ready to Pass Medicare Doc Bill

AP (Mar. 26, 2015) In rare bipartisan harmony, congressional leaders pushed a $214 billion bill permanently blocking physician Medicare cuts toward House passage Thursday, moving lawmakers closer to resolving a problem that has plagued them for years. (March 26) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins