Friday , December 4 2020

Mutated Gene Animals Show Why editing is not ready for human testing



big mistake

The scientific community largely condemned Hae Jiankui, a researcher who recently claimed that the use CRISPR modify the genomes of twins in China.

A key criticism was that the CRISPR effects are not understood well enough to guarantee the well-being of the twins. On Friday, The Wall Street Journal published a disturbing story about the unintended consequences of gene editing CRISPR been on animals, and it paints a portrait of the technology is not ready for human testing.

Side effects may include

WSJ article describes a number of examples of geneticists using CRISPR to change the animal's exhibit favorable characteristics.

In each example, editing work, but it also produced unintended side effects. Rabbits and pigs modified to grow slimmer as increased increased language and additional vertebrae, respectively. Goats modified to grow longer cashmere wool growing too large in the womb to natural childbirth, while the cattle that the scientists modified sports coat light calf died.

If we still can not prevent our CRISPR change from the production of these unintended consequences in animals, we certainly should not edit the human genes.

cranked Up

But we might not need to change the CRISPR genes to be useful. On Friday, researchers from the University of California at San Francisco published a study in the journal science in which they describe CRISPRa, variations in the CRISPR, which does not require any editing at all. Instead of cutting the target gene is modified the system enhances the activity of the gene.

The most common genetic mutation in severely obese people in SIM1 or Mc4r genes, both of which are important for the regulation of hunger and satiety. For their research scientists genetically engineered mice have a mutation in one of these genes. They then used CRISPRa, to enhance expression nya-mutated gene. This allowed the mice to effectively regulate your hunger, as if they had no mutation at all.

In the end, CRISPRa may allow us to address obesity and a variety of other genetic disorders in humans – all without the need to carry out risk editing of a single gene.


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