TOXINS MAY PASS DOWN THROUGH GENERATIONS

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TOXINS MAY PASS DOWN THROUGH GENERATIONS

 

http://www.surfingtheapocalypse.net/cgi-bin/forum.cgi?read=78360

 

Monday, 6 June 2005, 2:16 a.m.

 

Toxins may pass down generations

http://news.bbc.co.uk/2/hi/health/4605847.stm

 

Chemicals can change the way genes work

Toxic chemicals that poisoned your great-grandparents may also damage your

health, US research suggests.

 

A team from Washington State University has produced evidence that some

inherited diseases may be caused by poisons polluting the womb.

 

Research on rats indicates man-made environmental toxins may alter genetic

activity, giving rise to diseases that pass down at least four generations.

 

The research is published in the journal Science.

 

" It is a new way to think about disease. "

Dr Michael Skinner

 

The scientists exposed pregnant rats to two agricultural chemicals during

the period that the sex of their offspring was being determined.

 

The compounds were vinclozolin, a fungicide commonly used in vineyards,

and the pesticide methoxychlor.

 

Both are known as endocrine disruptors - chemicals that interfere with the

normal functioning of reproductive hormones.

 

Rats exposed to the compounds produced male offspring with low sperm

counts and poor fertility.

 

They were still able to produce young, however. When these rats were then

mated with females that had not been exposed to the toxins, their male

offspring had the same problems.

 

The effect persisted through at least four generations, impairing the

fertility of more than 90% of male offspring in each generation.

 

The researchers found the damage was not caused by alterations in the DNA

code, but changes in the way the genes work.

 

These epigenetic changes, as they are known, are caused by small chemicals

that become attached to the DNA, modifying its activity.

 

Epigenetic changes have been observed before - but were not previously

known to pass onto later generations.

 

Cancer clue

 

Lead researcher Dr Michael Skinner believes they may contribute to

diseases such as breast cancer and prostate cancer.

 

We need to find out whether this trans-generational effect is translated

to much lower doses

 

Professor Alan Boobis

Both diseases are becoming more common, and Dr Skinner says that cannot be

down to genetic mutations alone.

 

The researchers believe their findings suggest exposure to environmental

toxins may play a key role in the evolutionary process.

 

Evolution may not be driven entirely by genetic mutations, as commonly

thought.

 

Dr Skinner said: " It is a new way to think about disease. We believe this

phenomenon will be widespread and be a major factor in understanding how

disease develops. "

 

However, Dr Skinner stressed more work was needed to corroborate the

findings.

 

The levels of chemicals the rats were exposed to were very high - much

higher than people normally ever encounter.

 

Professor Alan Boobis, a toxicologist at Imperial College London, UK, told

the BBC News website the findings were interesting, but he said there was no

need for people to be alarmed.

 

" This effect is likely to be concentration dependent, and these animals

were exposed to very high levels of chemicals, " he said.

 

" We need to find out whether this trans-generational effect is translated

to much lower doses. "