Saturday, March 8, 2008

You And Me And Baby Makes Four

Okay, here's a little tidbit that's sure to get the giddy mad scientist in me excited and ready to rev up the plasma balls and Tesla coils, break out the microscope, and start doing bizarre and rebellious things with human reproductive systems.

Oh, and I might add before I start the meat of this blog post, let's be sure to clear the room of any neoconservative types, please. We wouldn't want any fundamentalists thumping their leather-bound holy books (why are the covers always black?) and ruining our scientific parade. I mean, really, if they get a whiff of what's going on in the hallowed halls of biology these days they might just, you know, insist that we keep living with our God-given diseases and disorders.

Now, having gone through six years of infertility treatments prior to the adoption of our two wonderful children, I can tell you with a certain degree of authority that there are some pretty unnatural yet clever ways of making babies that don’t in any way involve sexual intercourse. The most simple of these is artificial insemination (where the father – um, how should I say this? – "collects" his semen, and the concentrated "man-soup" is put into the female at just the right time and in just the right manner). If that fails, in vitro fertilization is an option (you know, "test tube babies", where eggs are surgically collected from the female, put into a Petri dish, washed with live sperm, and grown for a few days before being put into the mother's uterus). Yeah, we went through all that. Several times.

But reproductive biologists have gotten pretty good at the art of manipulating eggs, removing and even transplanting nuclei (where the DNA is located) between eggs, and adjusting the environment around the developing embryos. In fact, there's this little technique called Somatic Cell Nuclear Transfer (SCNT) which has bioethicists all in a tizzy, where you can remove the nucleus from an egg and replace it with the nucleus of an adult human, thus potentially cloning a person. Sounds like science fiction? Not at all. We can do it right now. We just don't. Because, like, that would be way too close to the plot of a bad B movie. And we wouldn't want to, say, remove stem cells from the embryo (which, at that point, looks more like a beach ball than a little human with a beating heart) and actually save lives.

Well, now some researchers are reviving the SCNT method.

But wait! Before you start shaking your head and calling up your Pentacostal buddies (I have one, too) and alerting FOX News, the new SCNT technique isn't for cloning purposes or harvesting stem cells or creating mindless replicas of Hitler or anything. Instead, this is a novel way to keep the potential child from developing mitochondrial disorders. And how do they achieve this lofty goal? By involving two mothers and one father!

Your typical egg is composed of a single nucleus that, once fertilized with sperm, has DNA from both the mother and father. The egg also has mitochondria, which are teeny-tiny structures that provide energy for the cell. Mitochondria also have DNA, but that DNA is solely derived from dear ole Mom. When the child grows up, he or she will have that Mom's mitochondrial DNA in every cell of their body, and none from Dad.

But if Mom's mitochondrial DNA is defective, harboring mutations that lead to a variety of diseases, heretofore there has been no way to prevent it from being passed to the child.

Using SCNT, though, researchers can remove the fertilized nucleus from the original Mom's egg and place that nucleus into the egg of another woman, whose nucleus had been removed. "The Other Woman" would have normal mitochondrial DNA. Thus, the resulting child from the fertilized egg would have the nuclear DNA (which make us who we are) from their traditional mom and dad, and mitochondria from woman #2. Voila! One father and two moms = healthy baby (and a bizarre family tree).

Wow. That gives a whole new meaning to the term "ménage tois"!

Image taken from HERE.


Sparkling Red said...

That's pretty amazing!

I love your illustrative photo with the cast of Three's Company. Hilarious. :-)

Hortense said...

Forget the ethical concerns. What about the impact to the genealogical software industry?!

Grad Student Without A Cause said...

My Bible is bound in burgundy leather. :)