Editing DNA for the treatment of genetic diseases

A team of scientists has taken an important step forward in the application of DNA therapy to replace faulty DNA with healthy DNA, paving the way for the treatment of genetic diseases in humans.

Researchers at the University of Bristol, Münster and the Lithuanian Institute of Biotechnology have observed the process by which an enzyme class called CRISPR is able to connect and alter the structure of DNA.

The results of using the CRISPR correction technique, published in the Proceedings of the PNAS Academic Academy, show that DNA editing tools can be used to heal genetic diseases in humans.

The first CRISPR enzyme was discovered in bacteria in the 1980s, which is considered to be a bacterial immune defense system against the onset of the virus. Recently, scientists have shown that a CRISPR enzyme, in particular Cas9, could be used to replace a defective gene in the human genome - capable of completing the genetic information genome in humans. .

Illustrations illustrate DNA attached to magnetic particles

CRISPR uses enzymes called "surgical tools" targeting the main targets in 23 pairs of human chromosomes, without producing unexpected mutations or defects.

CRISPR enzymes use the RNA molecule - a nucleic acid analogous to that in the DNA structure. The targeting process requires CRISPR enzymes to push the stranded DNA strands and replace them with RNA to form a specific sequence structure, called an 'R-loop'.

The team tested the R-loop model, using a special microscope to modify single-stranded DNA molecules that were prolonged in a magnetic field. By changing the twist on DNA, researchers can directly track the evolution of R-loop formation by single CRISPR enzymes. This allowed them to detect previous unknowns in the course of studying and exploring the effects of DNA sequencing.

Professor Mark Szczelkun, of the University of Bristol in Biochemistry, said: "The key challenge in exploiting this interesting genome editing tool is to ensure that only a specific position in the genome is the item. Molecular observations can show the effect of DNA sequences on the R-loops. In the near future, this tool will greatly assist in the proper restructuring of CRISPR enzymes, Correct and minimize unwanted effects on the target. "This is one of the key steps if we want to apply genetic modification tools to cure human genetic diseases."

According to ScienceDaily

26-12-2016 14:52:47