GENES: You aren't what you eat (sort of)

From: Robert J. Bradbury (bradbury@aeiveos.com)
Date: Sat Jun 09 2001 - 15:25:52 MDT


The June 2 issue of Science News (pg 342) has an summary of an article
in the June issue of Nature Genetics regarding the polymorphisms ('many
forms') of the promoter region of the UCP2 gene.

Now, "What is the UCP2 gene?" you may ask? (Prof. Bradbury hands
the wand of enlightnment to the cute girl who raised her hand
first...) UCP2 stands for "UnCoupling Protein 2". It is a protein
found in your mitochondria and functions to short-circuit the proton
gradient around the mitochondria. [The mitochondria pump protons
(H+ ions) out generating an electrical charge gradient. Normally
the protons run down the gradient back into the mitochondria through
ATP synthase to generate ATP. When the UCP proteins are activated
they open a channel to allow the protons to flow directly back into
the mitochondira without generating any ATP.] The UCP proteins are
typically activated to allow you to throw away excess energy (in
the process effectively generating heat).

The article discusses the fact that researchers in France and Austria
have identified genetic variations in the promoter region of the
UCP2 gene that result in people being more or less obese. Those
individuals who have more UCP2 burn more of their energy and store
less fat. Assuming a normal genetic distribution, that means there
will be people homozygous for more UCP2 production (e.g. thin),
heterozygous for an intermediate level of UCP2 (e.g. average) or
homozygous for minimal UCP2 production (e.g. overweight).

Obviously one can speculate on the functions of other UCP proteins
(there are at least 5 in the human genome) and interactions between
these and a host of other genes involved in nutrient absorption and
metabolic rates to provide a wide range responses to excess dietary
energy.

There is going to be one or more blockbuster drugs for the pharma
companies that figure out how to crank up the production of UCP2
or figure out how to force it to be on much of the time.

Robert
=======
Refs: (though you may need subscriptions to access the URL's)
"Gene variations police the storage of fat"
Science News 159:342 (June 2, 2001)
http://216.167.111.80/20010602/fob6.asp

"A common polymorphism in the promoter of UCP2 is associated with
decreased risk of obesity in middle-aged humans"
Esterbauer, H., et al.
Nature Genetics 28:178 (June 2001).
http://www.nature.com/cgi-taf/DynaPage.taf?file=/ng/journal/v28/n2/full/ng0601_178.html&filetype=pdf



This archive was generated by hypermail 2.1.5 : Sat Nov 02 2002 - 08:08:02 MST