He points out some of the dramatic downsides of the genetic research being done in humans and animals, cautioning that we need to proceed carefully. He also dismisses the argument that we are playing god or will systematically harming kids by our expectations. Most parents will make choices for their kids that expand their choices not shrink them.

The evolutionary consequences of genetic choice is full of unknowns because evolutionary science is full of unknowns and uncertainties. Genetic engineering could harm children and extinguish the "human race." It could enable states to engage in eugenics, requiring people to have better workers and soldiers. The basketball player Yao Ming is actually result of the Chinese encouraging too tall athletes to marry.

There are four basic principles to govern human genetic engineering:

1) Don't harm children. Parents should be allowed to genetically engineer children in any way they wish except in ways which expose the child to serious bodily or mental harm or impairment that is not outweighed by the potential benefit to the child.

2) Do not permit state-sponsored, unethical genetic engineering. There is no way stop states from competing in eugenic programs of genetic enhancement without such a treaty.

3) Don't terminate the human lineage. We need a branch of the federal government, for instance in the Public Health Service, charged with mitigating threats to humanity. Prevent existential risks to human life in general. Inbreeding could be a problem but we already have incest laws. Humanity could be engineered to the point that interferes with reproduction if parents choose mods that force their kids to only mate with other similarly modified kids. Loss of genetic diversity could result from everyone choosing the same genes.

4) Do not stifle progress towards understanding the universe. We need to prevent an anti-science backlash which would close down the fredom of research. Human-animal chimera research could provoke such a backlash. Scientists need to remain engaged with the public's "yuck factor."

We all stand at the beginning of a long line of future human/post-human descendents, just as we stand at the end of a line of ancestors. We owe it to both our ancestors and descendents to preserve that continuity.

Read George's notes here