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The Stem Cell Debate: Is it

Over?

Stem cell therapies are not new. Doctors have been

performing bone marrow stem cell transplants for

decades. But when scientists learned how to

remove stem cells from human embryos in 1998,

both excitement and controversy emerged.

The excitement was due to the great potential these

cells have in curing human disease. The

controversy centered on the moral implications of

destroying human embryos. Political leaders began

to debate on how to regulate and finance research

involving human embryonic stem (hES) cells.

The Ethical Issues

Until recently, the only way to get pluripotent stem

cells for research was to remove the inner cell mass

of an embryo and put it in a dish. The possibility of

destroying a human embryo can bedisturbin g, even

if it is only five days old. Stem cell research thus

raised difficult questions:

• Does life begin at fertilization, in the womb,

or at birth?

• Is a human embryo equivalent to a human

child?

• Does a human embryo have any rights?
• Might the destruction of a single embryo be

justified if it provides a cure for a countless

number of patients?

Problem Solved?

Newer discoveries may bring this debate to an end.

In 2006 scientists learned how to stimulate a

patient's own cells to behave like embryonic stem

cells. These cells are reducing the need for human

embryos in research and opening up exciting new

possibilities for stem cell therapies.

Both human embryonic stem (hES) cells and

induced pluripotent stem (iPS) cells are pluripotent:

they can become any type of cell in the body. While

hES cells are isolated from an embryo, iPS cells can

be made from adult cells.

With alternatives to hES cells now available, the

debate over stem cell research is becoming

increasingly irrelevant. But ethical questions

regarding hES cells may not entirely go away.

Some experts believe it's wise to continue the study

of all stem cell types, since we're not sure yet which

one will be the most useful for cell replacement

therapies.

An additional ethical consideration is that iPS cells

have the potential to develop into a human embryo,

in effect producing a clone of the donor. Many

nations are already prepared for this, having

legislation in place that bans human cloning.

Adapted from

<http://learn.genetics.utah.edu/content/stemcells/scissues.

Accessed Jan. 3, 2017.

Glossary:

Stem cell: Célula-tronco; bone marrow: medula; due

to: devido a; put it in a dish: colocar em um

recipiente de laboratório para pesquisa; thus: logo;

disturbing: perturbadora.

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