A New Technique for Human Genetic Modification?
A disturbing paper in the April 27 issue of Cell describes a novel technique for reproducing genetically modified animals, and suggests that it may point the way to modifying humans.
The process reported was demonstrated on mice, and was performed by Chinese scientists; there are 13 co-authors at five different institutions, in Shanghai, Xi'an and Nanjing. It builds on previous work to generate haploid embryonic stem cells (haESCs), which were derived from androgenetic blastocysts, so they have male characteristics and are known as AG-haESCs. These can then be used as sperm substitutes to create what the researchers call "semicloned animals" since they "were derived by combining an AG-haESC donor with a normal oocyte." Jinsong Li, one of the authors, is quoted in the press release:
"The current procedure to generate genetically modified animals is tedious and very inefficient. We thought if we can generate haploid embryonic stem cells and produce semicloned animals by simply injecting those cells into oocytes, we would be certain to get a transmission into offspring with limited breeding as half of the progeny will inherit the genetic modification."
Genetically modified mice have been a staple of research for a long time, so a more efficient method of reproducing them is a potentially significant advance. But the authors do not stop there. The second paragraph of the press release reads:
Not only will the advance make it easier to produce genetically modified mice, but it may also enable genetic modification of animals that can't be modified by today's means. The technique might ultimately be used in assisted human reproduction for those affected by genetic disease, the researchers suggest.
Monkeys are specifically mentioned in the paper as a possible target for inheritable genetic modification. The authors admit that "right now the haESCs are clearly not as good as sperm for the purposes of IVF" but close their announcement by stressing the potential advantages:
"A similar technique might be one day used to correct genetic disease in germ cells in humans to have a healthy baby for parents," Li said.
Perhaps the most disturbing aspect of this work is how fast they went to discussing human applications. There is no mention of caveats or ethical difficulties; it's as though human genetic modification was the goal all along.
Previously on Biopolitical Times: