Defence of the clones
Since Dolly the cloned sheep was created in 1996, stem cell technology has been the centre of an ethical debate that remains unresolved. Last weekend, it dominated much of the discussions at the 7th World Congress of Bioethics in Sydney. Supporters of stem cell technology say few medical technologies have held more medical promise, as stem cells can be used to replace damaged and diseased cells anywhere in the body. Its critics find the creation of embryos morally abhorrent, saying it is wrong to create a new life to save a life.
More practical problems are the possible misuse of the technology for genetic enhancement and the creation of designer babies that would increase social inequalities. Doomsayers also fear that lunatic fringe groups may use it to overrun the world with cloned Hitlers or bin Ladens. But apart from technical difficulties, because of differences in the environment of the womb and upbringing, the cloned Hitlers and Osamas would not act, think or even possibly look like the originals.
Such irrational fears are keeping popular opinion away from stem cell research. California has taken a big step in committing $ 3 billion on embryonic stem cell research, but given the potential of this emerging technology, more funding is needed. Most people tend to confuse reproductive cloning (creating a person from a cell) with therapeutic cloning (using cloning to isolate stem cells for healing) as both use techniques involving embryos. Few realise that stem cell research also involves the use of other types of cells besides embryonic stem cells, such as adult stem cells from humans or animals, or stem cells from foetuses, umbilical cord or amniotic fluid.
Because of the US government’s opposition to embryonic cells for research, much of the work in the US is focused on harvesting of stem cells from the bone marrow in adults, and even from umbilical cords, even though they are less versatile than embryonic cells. Such bans are unnecessary, say scientists, as unused embryos harvested for in-vitro fertilisation (IVF) for assisted reproduction can be donated to science instead of being destroyed, and stem cell banks can be established to reduce wastage.
Even with limited funding, scientists have had many successes in animal studies. Stem cell technology has been used for things as diverse as healing broken skulls (stem cells purified from fat have been used to heal injuries in living animals) to treating baldness (stem cells plucked from the follicles of mice can grow new hair when implanted into another animal).
There’s more. Last month, scientists in Israel created biological pacemakers for animals by implanting heart cells derived from human stem cells into their hearts. If the technique works in humans, electrical pacemakers would become obsolete. The same week, US scientists transformed stem cells into retinal cells, which, when transplanted into the eye, have the potential to reverse most common forms of blindness. Scientists also announced that cardiac patients would soon be able to repair and regenerate their hearts by using stem cells from their own organs. Europe had earlier successfully transplanted adult bone marrow cells into heart patients, but scientists say the heart-to-heart transfer offers better prospects for replicating the heart’s actions.
What helps scientists work wonders with stem cells is the fact that these foundation cells of the body can be developed into specialised tissues and organs. Stem cells can be used to generate healthy and functioning specialised cells, which can then replace diseased or dysfunctional cells that cannot heal naturally.
This bit of assisted healing — replacing diseased cells with healthy cells — is hardly different from organ transplantation, which is widely accepted throughout the world. Given the acute shortage of donors, stem cells are a great alternative to transplantation. Since stem cells can be modified into different functional adult cell types, it can be used for all diseases involving tissue degeneration, such as Parkinson’s and Alzheimer’s diseases, heart disease, spinal cord injury, stroke, burns, Type 1 diabetes, osteoarthritis, rheumatoid arthritis, muscular dystrophies and liver diseases. Stem cells technology has already been in limited use, and haematopoietic stem cells present in the bone marrow have been in use in bone marrow transplants for over 40 years.
While almost all countries oppose cloning to create a human being, opinion is starkly divided on whether to ban cloning of human embryos for stem cell studies or other medical research. The US is campaigning at the United Nations for a global treaty banning embryonic stem cell research and all forms of human cloning, but nearly 130 countries — including India — say that each nation should be allowed to decide for itself whether to regulate therapeutic cloning.
Most countries, including India, have already drafted guidelines for stem cell research that, among other things, bans aborting foetuses for harvesting stem cells. Considering its potential for healing, it will take more than George Bush’s moral police to nip stem cell research in the bud.