Writing in The Daily Telegraph, the Prime Minister said the process would not damage the countryside and cause only "very minor change to the landscape".
He added that it has "real potential to drive energy bills down" and insisted that the Government was not "turning our back" on low carbon generation but needed to secure a mix of energy sources.
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The controversial procedure involved nuclear DNA from the mother, mitochondrial DNA from a donor, and the father's sperm.
The move comes amid a boycott of the paper in Liverpool due to its controversial coverage of the 1989 Hillsborough disaster.
Glasgow East MP Natalie McGarry has been charged in connection with alleged fraud offences.