There was an
exciting scientific discovery very recently: mature cells, when immersed in a
dilute citric acid solution for half an hour, regress to the state of stem cells
which can subsequently be cajoled into turning into specialised cells, such as
a nerve cell or a liver cell. These ‘induced pluri-potent stem cells’ (iPSCs,
or just iPCs) are not new in themselves, having been around for a few years,
but we used to have to make them by manipulating their genetic make-up.
There’s no
huge surprises here really. All cells in your body contain the same DNA, so all
carry the genetic information needed to become any of the specialised cells.
When you’re still a tiny ball of cells 10 days after fertilisation, you’re made
of stem cells that are all alike but that start to differentiate into the
various specialised types of cells a bit later.
Now that a
dunk in a simple solution of a household chemical has replaced complex lab
procedures involving carrier viruses, a range of possibilities as to the use of
iPCs opens up. These cells may replace stem cells from discarded IVF embryos
and from embryos specially created for research. They also hold enormous
potential for eventual therapeutic applications, quite conceivably making organ
transplants a thing of the past in a few decades. (Need a new liver? We’ll take
some skin cells from you and turn them into liver cells and grow you one – and
because it’s truly yours, rejection won’t be a problem.)
But an iPC can
as easily be turned into a gamete-producing cell as into any other kind of cell.
A skin cell from a man can be turned into an iPC and from there into a
sperm-producing cell, or a skin cell from a woman into an egg-producing cell.
More interestingly, though, a woman’s
skin cell can be turned into a sperm-producing cell the same way, or a man’s can be turned into an egg-producing cell; we all carry the genetic
blueprints for both. (No, this isn’t a flight of fancy on my part, or an
attempt to usurp HG Wells or Dr Who as the king of sci-fi. It’s somewhere
between being on the horizon and just around the corner. Check it out on BioEdge at http://www.bioedge.org/index.php/bioethics/bioethics_article/10842)
So two
blokes, or two women, will be able to make babies by one of them producing
sperm cells and the other producing egg cells, in both cases from iPCs made
from cells taken from their bodies.
Those
gametes are then brought together through test-tube fertilisation and hey
presto, your baby, sirs or mesdames (well, in 9 months time, that is).
Will this
spell the end of sex, as in ‘men and women’? After all, if women can produce
sperm and men can produce eggs (albeit in a roundabout way), there seems little
point in continuing to differentiate between the two. We are still talking
about markedly different male gametes and female gametes, but there’s a twist: all
the sperm (rather than half) produced from a female iPC will carry the X
chromosome, while half the eggs produced by a male iPC will carry a Y
chromosome (as opposed to none of them). An embryo will still be male or female
depending on its chromosomal complement. However, we may well be talking about
the end of sex in the sense of male and female persons (as opposed to gametes) being required to produce a child.
If/when this
materialises, it will be a game-changer. One of the potent arguments against
same-sex marriage has hitherto been that a same-sex couple are incapable of
producing a child that is genetically related to them both. But if two guys or
gals can create a family in the biologically purist sense of the words – i.e.
by bringing about children of which both are the genetic parents – this
objection has the rug pulled from under it.
For a
lesbian couple, the situation seems straightforward: one provides the eggs and
another the sperm via iPCs made from their cells, an embryo is transplanted
into one of them, and she has a natural (well, almost) pregnancy and delivery. The
child will always be a girl, for there is not a Y chromosome in sight. For a
gay male couple, it’s not quite as simple. For one thing, there are both X and
Y chromosomes involved now, and so the ensuing embryos may be male or female. Pre-implantation
genetic diagnosis (PGD), already a well-established technology, can identify
the sex of an embryo as well as genetic abnormalities, and the unwanted ones
can be discarded. A quarter of those embryos will be duds anyway as they will
have two Y chromosomes, which is not viable; half will be male and a quarter
will be female (decisions, decisions). For another, they will have to get a
woman to transplant their embryo into, i.e. a surrogate (artificial wombs still
being quite some way off). So females will become independent of males in the
baby-making business, albeit only for the production of daughters; but males
remain dependent on females, if not for creating embryos of either sex, still
for seeing them through to becoming babies.
The
self-sufficiency of women in this regard has an interesting corollary: the
human species can theoretically be perpetuated without men. ‘Maleness’ as a
human trait can be restricted to sperm cells produced from iPCs made from
women’s cells – and none of those little wrigglers contain the ‘male’ Y chromosome.
With this technology, males are becoming surplus to requirements. As a bloke,
I’m about to become a biological redundancy, a vestigial add-on of purely
historical interest to human biology.
Alright, so
I’m exaggerating just a trifle for rhetorical effect, but there is a serious
message in all this. The genie is out of the bottle, and genies once released
are notoriously difficult to put back in. I do think it’s time for women in
particular to do some hard thinking about where all this is heading. What sort
of world do you want for your granddaughters?
Barend Vlaardingerbroek lives in
Lebanon and is a regular contributor to ‘Breaking Views’ on geopolitical and
social issues. Feedback welcome at bv00@aub.edu.lb.
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