CRISPR, a new way to edit genes, could become very useful for gene therapy. When I read these articles, I have to wonder however, if scientists are interested in curing patients or are more focused on understanding biology. It's great, that they want to understand diseases but one has to wonder, why they seem to love treating a disease and not preventing or curing it. I can give you a perfect example. The article says: "In future studies, the researchers plan to conduct genomewide screens of cells that have become cancerous through the loss of tumor suppressor genes such as BRCA1. If scientists can discover which genes are necessary for those cells to thrive, they may be able to develop drugs that are highly cancer-specific, Wang says." BRCA1 is a gene, that repairs DNA double strand breaks. If this gene is not working, more mutations occur and the risk for driver mutations and cancer increases up to a lifetime risk for breast cancer of 85% (at least this is, how I understood it). So a main goal should be, to replace the faulty BRCA gene because then DNA repair will function normally and cancer risk will be highly reduced. But instead of repairing the faulty BRCA gene and preventing breast cancer, they look at methods to improve chemotherapy and targeted cancer therapy. This is very important for already diagnosed breast cancer patients but it is a joke for any women with BRCA mutations because instead of preventing you from getting cancer, they only improve the therapy. And even if you are disease free after chemotherapy, with a BRCA mutation you are very likely to suffer from recurrence very soon. So it will be a cycle of cancer - therapy - cancer - therapy - cancer etc.. A much better approach would be: BRCA mutation - repair faulty BRCA gene with CRISPR - no breast cancer or highly reduced risk. Don't get me wrong, it's good if we have better therapies, but these therapies will take 10 to 20 to 30 years, if they are approved at all. In order to get rid of many health care problems, a much easier approach would be to do one thing: Look at healthy people, find out how healthy genes look like (we already know this to a high degree). Insert these healthy genes into ill people with high risk genes. Job done. There is no need to develop new genes or understand them to the molecular level. We just copy what nature already planned to keep humans healthy. http://web.mit.edu/newsoffice/2013/speeding-up-gene-discovery-1212.html Since the completion of the Human Genome Project, which identified nearly 20,000 protein-coding genes, scientists have been trying to decipher the roles of those genes. A new approach developed at MIT, the Broad Institute, and the Whitehead Institute should speed up the process by allowing researchers to study the entire genome at once. The new system, known as CRISPR, allows researchers to permanently and selectively delete genes from a cell’s DNA. In two new papers, the researchers showed that they could study all the genes in the genome by deleting a different gene in each of a huge population of cells, then observing which cells proliferated under different conditions. “With this work, it is now possible to conduct systematic genetic screens in mammalian cells. This will greatly aid efforts to understand the function of both protein-coding genes as well as noncoding genetic elements,” says David Sabatini, a member of the Whitehead Institute, MIT professor of biology, and a senior author of one of the papers, both of which appear in this week’s online edition of Science. Using this approach, the researchers were able to identify genes that allow melanoma cells to proliferate, as well as genes that confer resistance to certain chemotherapy drugs. Such studies could help scientists develop targeted cancer treatments by revealing the genes that cancer cells depend on to survive. Feng Zhang, the W.M. Keck Assistant Professor in Biomedical Engineering in the Department of Brain and Cognitive Sciences and senior author of the other Sciencepaper, developed the CRISPR system by exploiting a naturally occurring bacterial protein that recognizes and snips viral DNA. This protein, known as Cas9, is recruited by short RNA molecules called guides, which bind to the DNA to be cut. This DNA-editing complex offers very precise control over which genes are disrupted, by simply changing the sequence of the RNA guide. “One of the things we’ve realized is that you can easily reprogram these enzymes with a short nucleic-acid chain. This paper takes advantage of that and shows that you can scale that to large numbers and really sample across the whole genome,” says Zhang, who is also a member of MIT’s McGovern Institute for Brain Research and the Broad Institute. ... In future studies, the researchers plan to conduct genomewide screens of cells that have become cancerous through the loss of tumor suppressor genes such as BRCA1. If scientists can discover which genes are necessary for those cells to thrive, they may be able to develop drugs that are highly cancer-specific, Wang says. This strategy could also be used to help find drugs that counterattack tumor cells that have developed resistance to existing chemotherapy drugs, by identifying genes that those cells rely on for survival. The researchers also hope to use the CRISPR system to study the function of the vast majority of the genome that does not code for proteins. “Only 2 percent of the genome is coding. That’s what these two studies have focused on, that 2 percent, but really there’s that other 98 percent which for a long time has been like dark matter,” Sanjana says.