Featured Research

from universities, journals, and other organizations

Arsenic - Not The Same For Everyone

Date:
June 26, 2005
Source:
University Of Arizona
Summary:
Children with a particular genetic variation metabolize arsenic from drinking water differently than adults with the same variation. The findings have important implications for the safety of drinking water worldwide and the use of arsenic as a cancer drug.

Children with a particular variation in the CYT19 gene metabolize arsenic differently than adults with the same genetic variant, according to a new research report. The findings have important implications for the safety of drinking water worldwide and the use of arsenic as a cancer drug.

Arsenic, a heavy metal found around the globe, including the potable water supplies in many parts of Arizona and the West, has long been known to cause diseases such as circulatory and neurological disorders and cancer, predominantly of the skin, lung and bladder. In the body, arsenic is converted into different compounds, some highly toxic, through a series of biochemical reactions. It finally leaves the body in the urine.

The new research raises the possibility that the risk of developing arsenic-related disease is not the same for everybody because an individual's genetic makeup determines how the toxic metal is metabolized.

"Finding genetic determinants of arsenic metabolism may one day enable us to identify a super-susceptible group of people, and conversely, people who may be relatively resistant to the effects of arsenic," said Walter T. Klimecki, who led the research team. Klimecki is a research assistant professor of medicine at The University of Arizona's Arizona Respiratory Center and member of UA's BIO5 Institute.

The study is published in the current edition of Environmental Health Perspectives. Co-authors on the article are: Maria Mercedes Meza of the Sonora Institute of Technology (Mexico), Lizhi Yu, Yelitza Y. Rodriguez, Mischa Guild and David Thompson of the UA Arizona Respiratory Center and A. Jay Gandolfi of the UA department of pharmacology and toxicology.

The research is part of The University of Arizona's Superfund Basic Research Program, which is funded by the National Institutes of Health's National Institute for Environmental Health Sciences. The study was also supported by the Sonora Institute of Technology, Mexico.

Studying the distribution of arsenic metabolites in the body is important because they have different toxic potencies, said Klimecki. "Since we know that people carry different versions of DNA sequence for any given gene, we ask, 'Do people with one sequence variant metabolize arsenic differently than people with another sequence variant?'"

Klimecki and his coworkers found that the answer is yes.

The team analyzed arsenic levels in urine samples from 135 individuals from the Yaqui Valley in Sonora, Mexico, who were exposed to drinking water containing arsenic. The study participants ranged from 7 to 79 years in age. The researchers then analyzed DNA samples from the same individuals for variations in three genes known to play roles in arsenic metabolism. When they matched the arsenic levels in the urine samples to the variations in the genes, the researchers saw that the distribution of arsenic metabolites was different in urine samples from people with a certain variation of the CYT19 gene.

At that point, Klimecki's team was in for an unexpected discovery. When the team split up the data into different age groups, it turned out that the association between the particular form of CYT19 and altered urinary arsenic metabolites could only be found in children. Adults carrying the same variant of CYT19 do not metabolize arsenic differently. "Apparently the genetic variation affects arsenic metabolism only during childhood," said Klimecki.

This result could be important for cancer medicine, as arsenic is used as a drug in leukemia therapy. Individual differences in the way arsenic is metabolized could influence the drug's efficiency. "It sounds obvious, but researchers often fall into the trap of assuming that children are just miniature adults," said Klimecki. "Our data really shout out the pitfall in that."

###

Reference: Developmentally Restricted Genetic Determinants of Human Arsenic Metabolism: Association between Urinary Methylated Arsenic and CYT19 Polymorphisms in Children. Maria Mercedes Meza et al., Environmental Health Perspectives, Vol. 113, No. 6, June 2005.

-------------

Contact:
Walter Klimecki, 520-626-7470, walt@arc.arizona.edu

Related Web sites:
Walter Klimecki
http://bio5.org/bio5/database.php?cmd=fac&faculty_id=2957

BIO5
http://bio5.org

NIEHS Superfund Basic Research Program
http://superfund.pharmacy.arizona.edu

More information on arsenic
http://coep.pharmacy.arizona.edu/arsenic/index.html

Environmental Health Perspectives
http://ehp.niehs.nih.gov



Story Source:

The above story is based on materials provided by University Of Arizona. Note: Materials may be edited for content and length.


Cite This Page:

University Of Arizona. "Arsenic - Not The Same For Everyone." ScienceDaily. ScienceDaily, 26 June 2005. <www.sciencedaily.com/releases/2005/06/050625223204.htm>.
University Of Arizona. (2005, June 26). Arsenic - Not The Same For Everyone. ScienceDaily. Retrieved August 21, 2014 from www.sciencedaily.com/releases/2005/06/050625223204.htm
University Of Arizona. "Arsenic - Not The Same For Everyone." ScienceDaily. www.sciencedaily.com/releases/2005/06/050625223204.htm (accessed August 21, 2014).

Share This




More Earth & Climate News

Thursday, August 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

California Drought Stings Honeybees, Beekeepers

California Drought Stings Honeybees, Beekeepers

AP (Aug. 21, 2014) — California's record drought is hurting honey supplies and raising prices for consumers. The lack of rainfall means fewer crops and wildflowers that provide the nectar bees need to make honey. (Aug. 21) Video provided by AP
Powered by NewsLook.com
Thousands Of Species Found In Lake Under Antarctic Ice

Thousands Of Species Found In Lake Under Antarctic Ice

Newsy (Aug. 20, 2014) — A U.S. team found nearly 4,000 species in a subglacial lake that hasn't seen sunlight in millennia, showing life can thrive even under the ice. Video provided by Newsy
Powered by NewsLook.com
Unsustainable Elephant Poaching Killed 100K In 3 Years

Unsustainable Elephant Poaching Killed 100K In 3 Years

Newsy (Aug. 20, 2014) — Poachers have killed 100,000 elephants between 2010 and 2012, as the booming ivory trade takes its toll on the animals in Africa. Video provided by Newsy
Powered by NewsLook.com
Charter Schools Alter Post-Katrina Landscape

Charter Schools Alter Post-Katrina Landscape

AP (Aug. 20, 2014) — Nine years after Hurricane Katrina, charter schools are the new reality of public education in New Orleans. The state of Louisiana took over most of the city's public schools after the killer storm in 2005. (Aug. 20) 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:
from the past week

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