BRCA MUTATIONS

On a beach somewhere, 1987

It’s funny how cancer news comes in “clusters.”  In a recent blog I described how Angelina Jolie’s brave public discussion of her medical problems and her chosen solution to them had resulted in a cluster of articles about detection and prevention of OVCA and BRCA.  Now comes a half-dozen pieces on what appears to be the same study, by researchers at the Perlman School of Medicine at the University of Pennsylvania, which discusses the probability of getting either of these cancers if you have mutations in either or both of the BRCA  genes.  The project involved over 33,000 (nearly all white) women from 33 countries, which I guess should yield reliable statistics.  A woman with a mutation in BRCA1 has a 46% chance of developing breast cancer, 12% chance of developing ovarian cancer and 5% of  encountering both.  This leaves 37% cancer free.  In the case of a BRCA2 mutation the odds were 52% for breast cancer, 6% for OVCA, and 2% both; 46% got off scot free.  (Note that a statistician might quibble with my interpretation of these data; I got scorched once before, long ago, for making a similar interpretation.  Nevertheless, if you read the article you will agree.)

So, the obvious conclusion:  If you have any reason to suspect that you have either of these mutations, get tested.  Good reason for such suspicion would be a first degree relative – mother, sister, daughter – who had either type of cancer.   At the very least, ask your gynecologist, and insist that he/she give the matter some deep thought.  Gene sequencing is no longer the bank-breaker  it once was, especially since the outfit that had a patent on the technique was forced to cough it up.  Insurance companies should be required to cover this species of diagnosis, at least for women with elevated risk.

If you read the article, below, you will be tripped up and disconcerted by discussion of something called “clusters”.  Don’t bother to Google this concept; you will get everything you didn’t want, and nothing else.   Both BRCA1 and 2 genes are thousands of “letters” (nucleotides)  long, and apparently the disabling mutations tend to occur in discrete sections of the gene.   The practical significance of this discovery is not explained, but – as I’ve said many times before – the more we learn about this (you supply the adjective) killer, the better off we are.  Also mentioned is something called “mutations with nonsense-mediated decay” which, despite its humorous name, is bad.  I will try to figure that one out.

Here is the link:

http://www.healio.com/hematology-oncology/breast-cancer/news/online/%7B565b2918-c2eb-4b7e-9deb-25f024cf9a0d%7D/breast-ovarian-cancer-risks-vary-by-brca-mutation-location-type?sc_trk=internalsearch