The UK's
Independent reports that a gob-smaking breakthrough in genetic engineering has been developed based on research conducted at UC Berkeley. The technique dubbed "Crispr" derives from bacterial defense mechanisms against viruses has been hailed as a milestone in medical science because it promises an accurate and precise means of editing the DNA code in humans. Applications for treatment of hereditary diseases such as sickle-cell anaemia and Down syndrome or incurable virus infections like HIV are obvious. Up until this development substitution or modification of a human's genome was full of risk. Modified viruses used to insert DNA did so on a random basis. Crispr uses an exact RNA model of the desired code modification and an enzyme, CAS9, to line up the model RNA with the target sequence of the DNA molecule exactly. CAS9 cuts both strands of the double helix and the RNA sequence is inserted. In the laboratory the process is precise and repeatable. Professor Mello of U Mass Medical School, who won the 2006 Nobel Prize for Medicine for his genetic research called Crispr a "triumph of basic science...a tremendous breakthrough with huge implications for molecular genetics. It's a real game-changer." However, prospects of people demanding "designer babies" have made the process illegal in many countries including the UK and the United States. Some scientists believe it is only a matter of time before doctors performing in-vitro fertilizations will suggest eliminating genetic diseases from affected embryos using the Crispr process before they are implanted in the womb.
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This process was first identified by researchers at University of California, Berkeley in bacteria's natural immune defense against invading viruses. Last year a research team led by Jennifer Doudna published a seminal study showing that Crispr can be used to target any region of a genome in various species including humans. Several other teams have demonstrated the technique's accuracy in plants, worms, fruit flies, mouse embryos, and human stem cells in culture. The technique's ease of use and effectiveness made therapeutic application immediately apparent. Dr. David Adams, a DNA researcher at Wellcome Trust Sanger Institute in Cambridge said, "There have been other technologies for editing genomes but they all leave a scar behind or foreign DNA material in the genome. This [Crispr] leaves no scars behind and you can change individual nucleotides (G,T,A,C) of DNA--the letters of the genetic textbook--without any other unwanted changes." Finally, it really is a brave, new world.
