22 January 2015
The latest developments in the use of the CRISPR technique for genome editing have prompted the question of whether the potential implications for human applications should be discussed.
New research has shown that CRISPR can be used in mice to engineer out parental mutations early in embryo development. The researchers used the Cas9 enzyme and specifically designed guide RNA delivered to mouse egg cells at the same time as sperm cells to fertilise them, and created mouse embryos and live offspring with edited genomes.
Whilst not the focus of the research, the authors speculate that similar approaches ‘may one day enable human genome targeting or editing during very early development’ that could in turn ‘enable genomic surgery for gene repair during the initiation of embryogenesis’.
Lead researcher Dr Tony Perry told the BBC that the eventual potential applications in humans warranted discussion, and that the UK regulator the Human Fertilisation and Embryo Authority (HFEA) would need to be ready, saying: "There are heritable diseases coded by mutations in DNA and some people could say, 'I don't want my children to have these mutations…you can imagine people doing this soon”.
Whilst the science is by no means at this stage yet, Prof Robin Lovell-Badge of the UK Medical Research Council said he saw possible uses in creating germ-line therapeutics for men with harmful mutations, although in most cases IVF and and preimplantation genetic diagnosis (PGD)
Any form of germ-line manipulation (producing heritable genetic changes) in humans is currently illegal; the UK is currently moving towards a modification of the law that would exclude the creation of embryos with mitochondrial DNA from a third donor ‘parent’ from this prohibition. This is to allow women who carry serious mitochondrial mutations to have genetic children unaffected by severe mitochondrial disease, although some contest the validity of such a legislative change.
What is increasingly clear is that as genetic science advances, there is an ongoing need for consideration of the potential implications for health and society.
James Lawford Davies of legal firm Lawford Davies Denoon will be talking on Regulating the use of mitochondrial transfer at a forthcoming Life Sciences and Society seminar in Cambridge on 21 April 2015.