29 December 2011

Is it a boy? The foreseeable bad consequences of medical advances

There is a healthy debate over whether a lab that created an extremely infectious version of influenza ought to publish the genetic sequence. The debate speaks to a larger problem: sometimes, medical advances do the world a disservice. The medical field could use some soul-searching, just as physicists did in the wake of the Manhattan Project.

A few years ago, I read a neat research finding: in a pregnant woman, some of the fetus's DNA crosses the placenta and circulates in the mother's bloodstream. Drawing on this finding, some researchers developed a clever blood test that is allowing pregnant women to non-invasively screen their fetuses for Down Syndrome (whereas in the past, amniocentesis or chorionic villus sampling were the definitive screens). Good on them.

Yet other researchers have done gone a step further, offering both maternal blood tests and a maternal urine test that reveals a fetus's gender. One of these researchers, Prof. Diana Bianchi of Tufts University, justifies her development of a blood test because it will help mothers receive early warning about whether their children are at risk for genetic, sex-linked conditions such as hemophilia and congential adrenal hyperplasia.

This benefit strikes me as far too small relative to the tests' tremendous downside: it will greatly worsen the calamitous global phenomenon of the Missing Women.

The expected sex ratio at birth is 105 boys born for every 100 girls, or 1.05. Yet in some countries, the sex ratio at birth is quite skewed: for example, China's is 1.13 and Vietnam's is 1.12. What results is a demographic disaster, with over 100 million women missing worldwide (and a number of unhappy single men left in their wake). This glut of unmarried men may even contribute to global unrest, as unmarried men are more likely than married men to engage in armed conflict or become terrorists.

A renowned economist, Amartya Sen, established that cultural bias against women underlies the deficit. In countries where it is economically advantageous to have a boy, some families murder or neglect their infant girls or abort their female fetuses. Currently, ultrasonography is the only non-invasive way to determine the gender of a fetus. Some of the affected countries have forbidden ultrasound clinics from revealing a fetus's gender, and some intermittently crack down on those profitable yet illicit ultrasound clinics that flout the rules.

But a maternal blood test or urine test will prove impossible to regulate. Making it easier for mothers to determine gender will almost certainly lead to more female fetuses being aborted worldwide, with all of its concomitant problems. I would at the very least like to see a fraction of the proceeds for this blood test go to empowering women in affected countries (by boosting primary education and decreasing maternal and infant mortality), which would begin to help the problem. I doubt we will see it.

Some medical disasters are not easily foreseeable. For example, most leading orthopedists did not expect metal-on-metal hip replacements to become a massive fiasco. Yet developing a maternal blood test for fetal gender has so little justification and its ramifications are so potentially terrible that I believe its developers acted unethically. It's a shame that some scientific advances leave the world worse off than before, because I believe that scientific inquiry possesses a unique ability to make the world rather wonderful.