杏吧原创

SOMETIMES a technology seems so riddled with potential problems you wonder
why its creators began developing it. At first glance, the news that scientists
are trying to create eggs and sperm out of run-of-the-mill body cells looks like
a glaring example
(see 鈥淏irth of a miracle鈥�).

The idea is to enable women who cannot produce eggs or men with no sperm to
have children of their own courtesy of, say, a simple skin cell. So far, it
hasn鈥檛 gone beyond a few animal experiments. And the number of things that could
go wrong is vast. Real sperm and eggs put many of their genes into a mothballed,
or imprinted, state which will be hard to reproduce inside artificial eggs and
sperm. When a real sperm fertilises an egg, it supplies a piece of kit called
the centrosome, needed to ensure normal cell division. An artificial sperm will
not have this. And so it goes on.

So why bother? One answer lies with Adam and Joanna Rose, a brother and
sister conceived via donor insemination who are now bringing a case under the
Human Rights Act to find out about their genetic father. There is a powerful
argument for saying they have every right to know. The problem is that people
donate sperm and eggs on the understanding that they will remain anonymous. If
the case succeeds it could lead to a collapse in donations.

Suddenly, the idea of artificial eggs and sperm doesn鈥檛 seem so crazy after
all.