Human cloning has been used to create stem cells from adults for the first time, in a breakthrough which could lead to tissue and organs being regrown.
Using the cloning technique that produced Dolly the sheep in 1996, researchers were able to turn adult human skin cells into stem cells, which can grow into any type of tissue in the body.
They even used the cells of a 75-year-old man, raising the prospect of body parts being regenerated in old age.
The advance could lead to new tissue-transplant operations for a range of debilitating disorders, such as Parkinson’s disease, multiple sclerosis, heart disease and spinal cord injuries.
Last year, a team created stem cells from the skin cells of babies, but it was unclear whether it would work in adults.
However, a team of scientists from the Research Institute for Stem Cell Research at CHA Health Systems in Los Angeles and the University of Seoul said they had achieved the same result with two men, one aged 35, the other the 75-year-old.
“The proportion of diseases you can treat with lab-made tissue increases with age. So if you can’t do this with adult cells it is of limited value,” said Robert Lanza, co-author of the research, which was published in the journal Cell Stem Cell.
The technique works by removing the nucleus from an unfertilized egg and replacing it with the nucleus of a skin cell. An electric shock causes the cells to divide until they form a “blastocyst,” a small ball of a few hundred cells.
In IVF, a blastocyst is implanted into the womb, but with the new technique the cells would be harvested to create other organs or tissues.
The breakthrough is likely to reignite the debate about the ethics of creating human embryos for medical purposes and the possible use of the same technique to produce cloned babies — which is illegal in Britain.