Breast Cancer Genes Verdict a Triumph for Women
Posted by on June 19, 2013 - 8:56am

Geneticists, researchers, and patients joined in celebration over last week’s unanimous Supreme Court ruling involving the BRCA1 and BRCA2 genes, colloquially referred to as the “breast cancer genes.”  The Supreme Court ruled that Myriad Genetics could not patent the BRCA1 and BRCA2 sequence of genes, because patents cannot be placed on that which is created organically in nature.  This decision opens the door for researchers outside of Myriad Genetics to study these genes, providing more opportunities to discover early signs of breast cancer susceptibility.  Karuna Jaggar, Breast Cancer Action’s Executive Director reported that this ruling was, “a tremendous victory for women with a known or suspected inherited risk of breast cancer. Today, the Court righted a wrong and has put patients’ health before corporate profits.”

Prior to this ruling, bio-tech conglomerate, Myriad Genetics, held patents on the BRCA1 and BRCA2 genes, monopolizing the research that can be done on these genes, which are strong indicators of susceptibility to breast cancer. Myriad had used their patents to come up with its BRACAnalysis test, which searches for specific mutations in these cancer predisposition genes.  Women who show these mutations have a three to seven times greater risk of developing breast cancer.  Myriad’s previously established patents on these genes gave them exclusive rights to use this genetic test on these genes.  Now that the BRCA1 and BRCA2 genes are open to outside researchers, scientists can use these genes to determine increased risks of patients who may develop breast cancer, ovarian cancer, and other cancers that these genes may help indicate.

Angelina Jolie recently made headlines for deciding to voluntarily undergo a double mastectomy after learning of her own BRCA genes' mutations.  Jolie had paid a high price for this test, since Myriad had a monopoly on the market, driving up the cost.  So what does this mean for the average, non-Angelina Jolie woman? Well, now this test will be widely available for more women at a more affordable price (we don’t all have as deep of pockets as Jolie).  This ruling will not only open the door for more opportunities for preventative screenings for breast cancer, but it will set a precedent for the scientific community to collaborate on research towards the common good.

For more information on this court ruling, please refer to this posts's sources found here and here.

 

The debate on personalized genetic testing
Posted by on July 24, 2012 - 11:10am

An estimated 848, 000 men and 790,000 women will be diagnosed with some form of cancer this year according to the American Cancer Society.  New genetic sequencing technologies have made it possible to get personalized genetic tests to determine one’s risk for developing a disease, including many different types of cancers.  The goal of genetic testing is to utilize the results that may indicate the presence of a disease-associated gene mutation to determine appropriate preventative care or targeted treatments.

So why have experts from the American College of Obstetricians and Gynecologists  (ACOG) recommended against individuals using such technologies to provide answers about their personal genetic risks? To read more, visit the Oncofertility Consortium blogsite.

The mysteriously evolving Y chromosome…
Posted by on January 18, 2010 - 8:52am

I know what you’re thinking, this is a Women’s Health Blog - but we like men here too.  A recent study published in Nature (and featured in the New York Times) reveals some interesting new insight into the X-chromosome’s somewhat puny-looking counterpart.  Researchers Jennifer Hughes and David Page at the Whitehead Institute have discovered that the Y-chromosome appears to be evolving much faster than the rest of the genome.

Humans have 23 pairs of chromosomes (46 total); two of those chromosomes, called the sex chromosomes, are responsible for determining the sex of a human. Women have two of the same chromosomes, named X (see “What’s with the dancing X chromosomes?"), while men have one X chromosome and one Y chromosome, thus resulting in a mismatched pair.  Scientists have known for quite some time that the Y chromosome originally contained the same genes as the X chromosome, but has lost most of those genes through evolution.  Because of this, scientists have believed that the Y chromosome has been degrading through gene loss and has reached, or will reach a static state.

This new research however may prove otherwise.  In their study, Drs. Page and Hughes compared the genetic makeup of the human and the chimp.  Since chimps and humans shared a common ancestor just six million years ago, the differences in the genomes can help determine rates of evolution in the species.  The researchers found that while the chimp and human genomes differed in less than 1 percent of their DNA, comparison of the Y-chromosomes shows a difference of 30%.  This data indicates that this chromosome in particular is not static, but is in fact evolving at a greater rate than the rest of the genome.

The researchers suggest that some of this rapid evolutionary diversity might be attributable to differences in the mating patterns of humans and chimps and the large role of genes on the Y chromosome in sperm production.  A unique feature of the Y chromosome is that because it occurs in a mismatched pair with the X chromosome, it cannot exchange genes (called crossing-over) prior to meiotic cell division the way that the other twenty-two chromosomes do.   This places increased selective pressure on the Y chromosome, since a change in one gene must affect the reproductive fitness of the others.  In addition, the structure of the Y chromosome provides it with the opportunity to exchange genes with itself, which could accelerate the rate of change in its genetic sequence.

So does this mean that men are evolving faster than women?  No it doesn’t (sorry guys).  However, according to Andrew Clark, a geneticist at Cornell University (see NYT article), the rapid changes of the Y chromosome could have broader effects on the rest of the human genome.  Only further research will tell…