Precision Gene Editing

mpthompson writes "NewScientist.com is reporting that scientists at Sangamo Biosciences have developed a method of editing DNA mutations with unprecedented precision without weaving in potentially harmful foreign genetic material. Different combinations of amino acids are designed to latch on and cut the DNA at exactly the place where the mutated gene lies. This triggers the body's natural repair process which corrects the gene where the DNA was cut. The technique will be used to target diseases caused by single-gene mutations such as combined immune deficiency (X-SCID) - or bubble boy disease - and sickle cell anaemia."

Comments

with a PhD in Genetic engineering

[cinnamon colbert]

I have not read the article, but repair processes can be "error prone". That is, the mechanisms cells use to repair DNA often involve high error rates.

The human genome is 3e9 BP long (roughly..not counting indels, the unsequenced centromeres, etc etc)

So the chemical process of identifying the one single mutated basepair has to have a chemical specificity of >>1e9, because there are >>1e6 cells that are exsposed. That is, lets say you feed the reagent to a person. Millions of cells, each with 1e9 bp, are expsosed. Say the process has an error rate of 1e10 - many, many cells will have incorrect repairs done
This is just like error rates in, say, reading data from a harddrive: the larger the file, the lower the error rte has to be

What /.ers may not appreciate is that typically, it is VERY, repeat VERY hard to get chemcial reaction specificity of anywhere close to 1e9 for reactions invovling DNA.

I will rtfa,