People aren't against stem-cell research because they think it's playing god, they are against it because they think that embryos have the moral worth of adults. Perhaps you are thinking about the arguments against cloning?
Incidently, stem-cell research has high potential but is also highly speculative. Similarly, gene therapy (using viruses to deliver gene fixes into the body of cells) was and is considered to have enormous potential with very similar hype to stem-cells. But after 35 years and billions of dollars of work, the the actual number of people who have been helped is very small.
Incidently, stem-cell research has high potential but is also highly speculative. Similarly, gene therapy (using viruses to deliver gene fixes into the body of cells) was and is considered to have enormous potential with very similar hype to stem-cells. But after 35 years and billions of dollars of work, the the actual number of people who have been helped is very small.