Gene editing tools cause genes in adult monkeys' livers to fail.

For the first time in adult monkeys, U.S. researchers have used a gene editing tool in adult monkeys to "hold back" a gene in the liver, lowering cholesterol levels in the monkeys' blood and suggesting that they can treat heart disease, Science daily reported Monday.
, the study paves the way for the treatment of certain genetic diseases caused by defective proteins.
it's not uncommon to make genetic edits on primates, but the researchers hope to send CRISPR and other gene editors directly into patients to correct mutant genes or otherwise treat diseases.
In the latest study, James Wilson, a gene therapy researcher at the University of Pennsylvania, and colleagues wanted to target PCSK9, a protein that blocks the removal of harmful low-density lipoprotein (LDL) cholesterol in the blood, while high levels of LDL cholesterol increase a person's risk of heart disease or stroke.
Wilson's lab has done so with the help of adeno-associated viruses (AVs), which deliver gene editing tools to cells that cut genomes at specific locations so that cells cannot be properly repaired, rendering genes out there. in the latest study,
, Wilson's team used AAV to deliver a gene-editing tool, large nuclease, toward rhesus monkeys. Four months later, 64 percent of liver cells carried the PCSK9 gene that six rhesbames had been eliminated,
the team said.
, at the highest dose, the concentration of PCSK9 protein in animal blood decreased by 84%;
nuclease treatment does lead to elevated liver enzymes, which suggests an unexpected immune response, and it cuts at sites outside the PCSK9 gene, which can cause cancer.
, Wilson believes, that as technology continues to improve, this PCSK9 gene-editing therapy could be offered to patients with high cholesterol heart disease, which also has the potential to treat metabolic diseases such as amyloid degeneration.
, however, UPenn cardiologist Kieran Msanru points out that Wilson's approach also has competitors: some companies recently announced that they have reduced the concentration of thyroxine, a amyloid protein, by 80 percent in monkeys, and that the company's methods are safer.
While Wilson's research is "exciting, it's too early to tell which method could be applied to humans."
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