Science

Breakthrough in chemical surgery brings hope of potential treatment to genetic mutations

By Sophie King

Scientists have discovered a breakthrough in “chemical surgery” that will be able to correct a type of genetic mutation in DNA behind a host of diseases.

Hope of potential treatment for a number of diseases has been brought by fresh DNA base editing because of a single genetic ‘misspelling’.

Scientists are positive that this new approach could offer new ways to understand certain human genetic disease by correcting mutations in a patient’s body.

Humans have tens of thousands genetic variations that are linked with disease and a large proportion of these arise because of a genetic “misspelling”.

To explain this further, it means that there is an error in one of the parts of the DNA double helix.

Pairs of molecules known as “bases” come in four forms dubbed as A (adenine), T (Thymine), C (Cytosine) and G (Guanine), which every living being is made up of.

However, about half of the known point mutations that are linked to diseases are down to the bases being mixed up – bases that are meant to be G become A and their corresponding pair being T instead of C.

Luckily, scientists can now say that these errors can be fixed using a process called “base editing”, turning the bases from A back to G, and T back to C.

Base editing is the process in which scientists have said they will now be able to fix the errors in a process, which will turn A bases back to G and T bases back to C. This will be done by using a modified version of the gene editing tool Crispr-Cas9.

The traditional Crispr-Cas9 has fewer advantages compared to the modified version. The newer version is less prone to problems of random insertions or deletions and works well in adult cells.

Mr David Liu, co-author of the new research from the Broad Institute of MIT and Harvard explains that he and other scientists are using base editing to try to study potential future therapeutic treatments for varying diseases.

However more work will be needed to “cure” disease, Liu Warns, “there are many additional steps beyond simply making the mutation that may be needed to treat disease.”

Developmental geneticist, Robin Lovell-Badge explains, “Many genetic diseases are due to mutations where a single base pair has been substituted for another.”

He says that it makes new base editing methods worth great value to make disease models and to hopefully correct genetic disease.

Darren griffin, a geneticist at the University of Kent, has suggested that the research could lead to improvements in cultures for embryos which might improve IVF. However, he also stated that it is less likely to be used to fix genetic errors in human embryos destined for birth. This is because embryo screening can already allow doctors to select embryos without harmful mutations.

Nevertheless, Liu says hopefully DNA base editing will enable an especially broad set of potential research and therapeutic applications in the future.

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