A new landmark stem cell technique in therapeutic cloning opens new horizons in treating rare diseases and disorders caused by gene mutations. Yet, like any kind of human cloning, the research has sparked controversy on either side of the Atlantic.
A decade-long effort of geneticists worldwide has finally been
crowned with success. On May 15, The Cell published report from scientists in
Oregon that they have managed to harvest stem cells from six human
embryos bred from donated eggs.
Two embryos got DNA of a child with a genetic disorder (samples
taken from skin cells), and the other four were raised with DNA
from fetal skin cells.
Shoukhrat Mitalipov, senior scientist at Oregon Health &
Science University, has announced elaboration of a breakthrough
technology enabling production of personalized stem cells to cure
illnesses with this unique human tissue.
“This [research] represents an unparalleled achievement. They
succeeded where many other groups failed, including mine,” stem
cell biologist George Daley of the Harvard Stem Cell Institute
shared with Reuters.
Some illnesses are caused by genetic disorder, by mutations in
mitochondria genes which power cell development. The new technique
makes it possible to replace defective with healthy ones by
supplying tissue with new mitochondrial genes.
Stem cells can develop into any of the over 200 types of tissue
in a human body and replace the diseased tissue with new healthy
cells.
Mitalipov and his team have come a long way to achieve the
long-expected positive result so much anticipated by the developing
stem-cell medical fraternity.
It took six years of experiments with monkey embryos to get
positive results with human ones. In 2009, they cloned Macaque
monkey twins Mito and Tracker, which brought them worldwide fame
for being the first to develop the technology of transplantation of
chromosomal complex into primates’ eggs, thus making cloning of a
primate – and potentially a human — possible.
At the same time Mitalipov particularly stressed that human
embryos made with his technique could not be developed into cloned
babies and he has no desire to check this out.
In September 2010 the US Clinical Events Committee granted
Mitalipov’s team a license to work with human eggs and embryos.
Then there were over two years of hard work that finally ended with
a genetic technology breakthrough.
In word the technique is ‘simple’. DNA from a patient is
implanted into a human egg, which develop into an early embryo with
patient’s DNA. Then the embryo is used to obtain stem cells for
treatment of such diseases as multiple sclerosis, Parkinson’s
disorder, various hereditary heart diseases etc.
The greatest achievement of the method is that the tissues
developed with the help of such cells will not be rejected by the
patient’s immune system because the genetic match of the tissue
will be flawless.
Also, the technique could be put to good use to help potential
parents to conceive an absolutely healthy baby without any genetic
defects that might endanger the child’s life or make things
difficult for the parents if the baby has health problems.
If the results of Oregon research can be repeated in other
genetic laboratories, the technique will become the third known
method to produce stem cells. One of the other two methods is
obtaining stem cells from early human embryos (blastocysts), in
large quantities raised in fertility clinics
(1998). Another one is the
way the famous sheep Dolly was cloned in Scotland back in 1996,
when scientists removed DNA from a sheep oocyte (egg), replaced it
with DNA from a sheep mammary gland cell and made it grow without
being fertilized with sperm.
But like many biotech technologies this one has its dark side,
too. The matter is that stem cells harvesting involves destroying
of cloned human embryos, a controversial method with far-reaching
consequences. Many find such approach unethical and in the face of
possible human cloning — even dangerous.
The director of education for National Catholic Bioethics
Center, an independent think tank in Philadelphia, Rev. Tad
Pacholczyk, told Associated Press that the method involves
utilization of “early human beings as repositories for obtaining
desired cells.”
“You’re creating them only to destroy them,” Pacholczyk
said, reiterating Catholic Church’s opposition to embryo
cloning.
Marcy Darnovsky, executive director of the Center for Genetics
and Society in Berkeley, California, shared with AP that she is
glad that Mitalipov is not interested in cloning babies. But the
report in The Cell is yet another good reason for the US Federal
government to ban human reproduction cloning once and for all, she
said.
Same critics come from the other side of the Atlantic, where the
British Human Genetics Alert watchdog group protested Shoukhrat
Mitalipov’s research even before the study was published in The
Cell.
The group’s director Dr. David King acknowledged that scientists
have finally delivered a method for reliably creating cloned human
embryos.
“This makes it imperative that we create an international
legal ban on human cloning before any more research like this takes
place. It is irresponsible in the extreme to have published this
research,” King told Reuters.
This article originally appeared on : RT