Transcript bmt challenges to biomedical research 3

CHALLENGES TO
BIOMEDICAL RESEARCH
Evaluate Therapeutic vs. Reproductive Cloning
HISTORY of CLONING
 Dolly the sheep – first cloned mammal in 1997
 Very few scientists believe human cloning (reproductive
cloning) should be permitted
 Many scientists in favor of therapeutic cloning – the
procedure used to produce embryonic stem cells that
theoretically can be used to treat diseases
WHAT IS A CLONE?
 Clone = precise genetic copy
 Reproductive cloning is really somatic cell nuclear transfer
(SCNT)
 In therapeutic cloning, the embryo is not placed in a
surrogate, but rather, undergoes cell division in the lab until
it reaches blastocyst stage
Obstacles to
Reproductive Cloning Using Animals
 Success rate very low
 Vast majority of problems occur during fetal development
 Additional problems show up after birth and years later
 “Large offspring syndrome” = cloned newborns 20-30%
larger than usual, making it hard to deliver unborn babies
EMBRYONIC and ADULT STEM CELLS
 Adult stem cells
 Embryonic stem cells
DIFFERENCES…
 Between reproductive cloning, therapeutic cloning,
and stem cell research:
 Goal of reproductive cloning is to create a new organism,
human or animal
 Goal of therapeutic cloning is to produce embryonic stem
cells
HUMAN STEM CELL RESEARCH
 2001 legislation allowed federal funding of research using 64
existing human embryonic stem cells
 Same legislation declared no federal funds for additional
research.
THERAPEUTIC POTENTIAL of
STEM CELLS
 Researchers must use existing human stem cell lines for research or
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find private funding sources
Creation of embryonic stem cells does not use fertilized egg
On the other hand, it does have the potential to become a living thing
if transplanted into the uterus
Question – is life destroyed if the stem cells are removed from the
blastocyst four days later?
Real advantage of stem cells – permits the production of perfectmatch tissue
Scientists have found that embryonic stem cells pick up cues from
neighboring cells and differentiate into that cell type
Scientists hope stem cells will be used to treat heart disease,
Parkinson’s disease, other disorders of the nervous system
OBJECTIVE 5:
Debate pros and cons
of
animal research
and
animal rights.