Chemotherapy in Parents May Make Offspring's DNA Unstable & Riddled With Mutations

By Sarah Zhang | February 1, 2012 9:02 am

spacing is important

Chemotherapy is poison that happens to kill cancer cells faster than it kills healthy cells; that it wreaks havoc on the bodies of patients is unsurprising. But chemo may also affect their unborn children. According to a new study in PNAS, the offspring of mice treated with chemotherapy have higher rates of mutation, even though the offspring themselves were never exposed to the drugs.

The results suggest that these mutations arise from genome destabilization caused by exposure to chemo, rather than just mutated sperm from the treated father. Male mice in the study were exposed to one of three common anticancer drugs—cyclophosphamide, mitomycin C, or procarbazine—and then allowed to mate with untreated females. After sequencing a small piece of DNA from the offspring, the researchers found that mice with treated fathers had mutation rates up to twice that of mice with untreated fathers. Notably, these mutations were present in DNA inherited from both the treated father and untreated mother.

What this likely means, according to the researchers, is that chemotherapy induces epigenetic changes in the sperm. Epigenetic changes don’t affect the underlying DNA sequence, but they alter chemical tags that control how genes are expressed. This in turn lead to genome destabilization in the offspring, allowing sequence mutations to arise in DNA from the mother or father. The exact mechanism for genome destabilization and how it’s inherited is unknown.

Lead author Yuri Dubrova is also cautious about how this data translates to humans. Since most cancer patients are too old to reproduce or are sterilized by treatment, childhood cancer survivors seem to be the only group this can potentially affect. Because of their short life span, the mice in this study reproduced only a few months after chemotherapy, but humans would likely have years in between. If the phenomenon applies to humans though, the nasty effects of chemotherapy might be longer-reaching than we realized.

[via Nature News]

CATEGORIZED UNDER: Health & Medicine
  • Hmmm

    In humans, males can reproduce very late in life. In American society, this is not the norm, but it can happen. Now was this just chemo without the addition of radiation?

  • http://www.chemotherapyfacts.com chemo

    exactly my thoughts too… was it without the addition of radiation? can someone reply?

  • PJ

    @Hmmm, Given that radiation wasn’t mentioned, and that they used the word ‘poison’ in the opening, I’d be inclined to say yes, as they’re two entirely separate beasts.

  • http://www.realrawhealth.com Kimmi

    Doesn’t the implication that cancer only affects children and old people sound off to anyone else?
    The results of this study have serious implications for humans of all ages.

NEW ON DISCOVER
OPEN
CITIZEN SCIENCE
ADVERTISEMENT

Discover's Newsletter

Sign up to get the latest science news delivered weekly right to your inbox!

80beats

80beats is DISCOVER's news aggregator, weaving together the choicest tidbits from the best articles covering the day's most compelling topics.
ADVERTISEMENT

See More

ADVERTISEMENT
Collapse bottom bar
+

Login to your Account

X
E-mail address:
Password:
Remember me
Forgot your password?
No problem. Click here to have it e-mailed to you.

Not Registered Yet?

Register now for FREE. Registration only takes a few minutes to complete. Register now »