Radiation causes genetic mutations in next two generations, in murinestudy

[John Jacobus <crispy_bird@YAHOO.COM>]

Found this through another list server, and thought it

would be of interest.



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

Radiation causes genetic mutations in next two

generations, in murine study

9/8/04

By: Reuters Health



LONDON (Agence de Presse Medicale for Reuters Health),

Sep 8 - Radiation exposure causes a high rate of

genetic mutations for at least the next two

generations, according to findings from a mouse study

presented at the Children with Leukaemia conference in

London on Tuesday.

Yuri Dubrova, Professor of Genetics at Leicester

University, central England, said: "We have obtained

the first experimental evidence that germ-line

mutation rates in unexposed offspring of irradiated

male mice do not return to normal unexposed mutation

rates but are very similar to that of the irradiated

males.



"Our results show that radiation-induced instability

can be transmitted for at least two generations after

initial paternal exposure to either fission neutrons

or X-rays."



The Ukrainian researcher told APM that the mutation

rate in the offspring of exposed male mice was three

to four times higher than in controls in many

different cell types, including bone marrow and sperm.





The high mutation rate persisted not only in the first

but also the second generation of mice. "This goes

against all predictions of classical radiation

biology. My major concern is to analyze why," he said.



Dr. Dubrova's group has also monitored

radiation-induced mutation in humans and studied

germ-line mutations among families from rural areas of

Ukraine and Belarus, which were heavily contaminated

by fallout from the Chernobyl disaster.



They found a statistically significant 1.6-fold

increase in mutation rate in the germ-line of exposed

fathers whereas the maternal germ-line mutation rate

was not elevated.



Commenting on the results, Dr. Dubrova said:

"Experimental evidence for radiation-induced mutation

in the human germ-line remains highly controversial.

But our studies in Ukraine and Belarus have shown that

genomic instability can be induced in the paternal

germ-line in humans. 



"It remains to be seen whether this instability can be

transmitted to further generations, as has shown to be

the case in our mouse studies."



A previous case-control study has suggested that

occupational exposure of fathers working at the

Sellafield nuclear reprocessing plant in Cumbria,

north-west England, could explain a cluster of

childhood leukemia cases in the nearby village of

Seascale.



However other studies have failed to find any effect

of paternal preconceptional irradiation.



By Richard Woodman



Last Updated: 2004-09-07 12:22:37 -0400 (Reuters

Health)





=====

+++++++++++++++++++

"A devotee of Truth may not do anything in deference to convention.  He must always hold himself open to correction, and whenever he discovers himself to be wrong he must confess it at all costs and atone for it."

Monhandas K. Gandhi, in "Autobiography"



-- John

John Jacobus, MS

Certified Health Physicist

e-mail:  crispy_bird@yahoo.com





	

		

__________________________________

Do you Yahoo!?

New and Improved Yahoo! Mail - 100MB free storage!

http://promotions.yahoo.com/new_mail 

************************************************************************

You are currently subscribed to the Radsafe mailing list. To

unsubscribe, send an e-mail to Majordomo@list.vanderbilt.edu  Put the

text "unsubscribe radsafe" (no quote marks) in the body of the e-mail,

with no subject line. You can view the Radsafe archives at

http://www.vanderbilt.edu/radsafe/