#CRISPR DNA Editing Corrects Disease Gene in Human Embryos - Experts Available @UofUHealth

Shoukhrat Mitalipov is the first U.S.-based scientist known to have edited the DNA of human embryos.		
	OHSU  Kristyna Wentz-Graff

The researchers, led by Shoukhrat Mitalipov at the Oregon Health & Science University, say their results suggest CRIPSR could be a powerful technique for correcting disease-causing genetic mutations in developing human embryos.

Scientists have successfully used CRISPR, a tool that cuts DNA with more precision than any other genome editing technology, to fix a genetic defect in human embryos that can cause serious heart problems, according to a landmark new study in the journal Nature.

They targeted a gene mutation that causes a heart-weakening disease, hypertrophic cardiomyopathy, that affects about 1 in 500 people. There are two major scenarios in which editing the DNA of an embryo might be considered ethical: One in which both parents carry a gene for a genetic disorder recessively, and one in which one parent carries a dominant gene for a disease, like hypertrophic cardiomyopathy or Huntington's disease.

In theory, interventions like this could be used to correct disease-causing mutations in IVF embryos before they are implanted, preventing genetically inherited diseases being passed down the generations.

Currently, the United States has barred the use of federal funds for embryo research and the U.S. But such clinical applications are still a long way off, and the researchers say this approach still needs to be tested for accuracy and safety.

The hottest invention in biology, CRISPR allows scientists to cut out and replace genes.

The new study is a significant advancement from the first experiments on human embryos using CRISPR. The donated human eggs and sperm cells carried the mutation. Chinese scientists conducted a similar experiment using CRISPR on embryos in 2015, but those embryos reportedly resulted in something called "mosaicism", which are off-target genetic mutations that happen when the changes to DNA are adopted by only some of the cells. The report said if the technology can not be legally harnessed to prevent more questionable uses - such as the creation of so-called "designer babies" with desirable traits - it should remain off limits.

However, the technology was only successful on 50 percent (projected up to 74%). At the same time, the eggs were injected with gene editing tools.

The procedure involved "correcting" the DNA of one-cell embryos using CRISPR to remove the MYBPC3 gene.

Additionally, we're at least decades away from having gene therapy techniques like this one become the norm.

A scientific breakthrough in OR that offers hope to those with genetic defects that cause deadly diseases faces steep hurdles to be tested. This is why scientists have not been allowed to develop over a few days.

Though gene-editing could potentially cure a number of diseases - including various cancers, sickle cell anemia, Tay-Sachs and cystic fibrosis - scientists have proceeded cautiously to avoid introducing unintended mutations.

"The question that will be most debated is whether the same principle of modifying the genes of an embryo in vitro is acceptable", analyzed by an independent expert, professor Darren Griffin (University of Kent), quoted by the Science Media Centre.

And Congress has banned the US Food and Drug Administration (FDA) from even considering the possibility of human clinical trials involving embryos with edited inherited genes. Tests now exist to diagnose many diseases prior to birth; however, at this time, there is no therapy in use that actually alters the DNA of embryos prior to birth. Earlier this year the National Academy of Sciences and the National Academy of Medicine said it supported the work in the US but only under very strict regulations.

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