Editing Our Genes?

A study published in Nature Biotechnology and also described in this article from The Independent, seems very exciting for genetic disorders!

Scientists used a genome-editing technology called Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) to cure adult laboratory mice of an inherited liver disease called type 1 tyrosinemia.  This condition can be found in both animals and humans (it affects about 1 in 100,000 people and is part of newborn screening panels in some states) and is related to liver metabolism.  Affected individuals are unable to break down the amino acid tyrosine and require a special diet and medication to prevent liver, kidney and brain damage.

The CRISPR technique enables researchers to snip out a mutated piece of DNA and replace it with the correct sequence.  In this instance, the researchers were able to correct a single “letter” of the genetic alphabet which had been mutated in the gene involved in liver metabolism.  They altered the genetic make-up of about a third of the liver cells in the mice through a high pressure intravenous injection and the researchers effectively cured the mice.

The fact that this technique can be used successfully in an adult animal could lead to the ability to use the technique in humans (probably after lots of ethics committees and institutional research boards weigh in on it and, of course, oodles of clinical trials are performed).  It might be a long wait, but it sure is exciting to think about how a future gene therapy might fix the genetic defect in people with MCADD that prevents them from making the enzyme that allows them to break down medium chain fats.

Science is amazing!