Scientists edit human genes for the first time ever in the US

Scientists have genetically engineered a human embryo for the first time in the US.

The technology allows for the editing of genes in a human embryo that could theoretically be allowed to develop into a full person, according to Oregon Health and Science University (OHSU) in Portland, which carried out the research.

The research isn't the first time that a human embryo has been genetically engineered. But no experiment ever before has worked on so many embryos, or done so with such safety or efficiency, according to the MIT Technology Review, which first reported the breakthrough.

The embryos were destroyed after just a few days, according to researchers.

Some countries have signed a convention prohibiting the practice on concerns it could be used to create so-called designer babies. Scientists are allowed to work on such experiments in Oregon so long as they're not allowed to fully develop and don't use public money.

Results of the peer-reviewed study are expected to be published soon in a scientific journal, according to OHSU spokesman Eric Robinson.

The research, led by Shoukhrat Mitalipov, head of OHSU's Center for Embryonic Cell and Gene Therapy, involves a technology known as CRISPR that has opened up new frontiers in genetic medicine because of its ability to modify genes quickly and efficiently.

CRISPR works as a type of molecular scissors that can selectively trim away unwanted parts of the genome, and replace it with new stretches of DNA.

Scientists in China have published similar studies with mixed results.

In December 2015, scientists and ethicists at an international meeting held at the National Academy of Sciences (NAS) in Washington said it would be "irresponsible" to use gene editing technology in human embryos for therapeutic purposes, such as to correct genetic diseases, until safety and efficacy issues are resolved.

But earlier this year, NAS and the National Academy of Medicine said scientific advances make gene editing in human reproductive cells "a realistic possibility that deserves serious consideration".

Additional reporting by Reuters