Transcript Designer Babies

Genetic Engineering:
Designer Babies
By: Jennifer
JV
Van
What are Designer Babies?
• Refers to genetic interventions into preimplantation embryos in the attempt to influence
the traits that the resulting offspring will have
• Term used by journalists, not scientists
• More realistic term: “Selected Baby”
• Currently not attainable, however advanced
technologies can be used to select the sex of your
future offspring as well as the ability to screen for
certain genetic defects (only legal in certain
countries)
Designer Babies
Pros
• Enable parents to avoid the
hardships and economic
burdens that accompany the
birth of a child with an
incurable disease
• New & Better genes passed
on to others
• Ability to enhance muscles,
height, intelligence
• To choose the sex, hair colour
and even personality of our
children
Cons
• Demeans the uniqueness
of each individual
therefore undermining
humanity
• Provides those with an
unfair competitive
advantage over the unenhanced
• Widens the existing social
gap between those who
can and cannot afford the
new treatment
Pre-Implantation Genetic
Diagnosis (PGD)
• An in vitro fertilization technique in
which embryos (an unborn offspring
in the process of development) are
created outside the womb and can
then be tested for genetic disorders
and gender
• Unfertilized eggs will be removed
from the patient, fertilized in a petri
dish and then brought to a zygote
(eight-cell) stage at which point cells
are removed and then tested using
PGD
• Reduces the chances that a child will
be born with a genetic disorder
Using PGD for Sex Selection
• The researchers at the Genetics & IVF Institute in
Fairfax took advantage of a simple rule in biology:
girls have two X chromosomes whereas boys have
one X and one Y chromosome
• In order to choose the sex of the offspring, the
power lies within the father’s sperm
• Y chromosomes have less DNA than X’s
• So, by staining the sperm’s DNA with a nontoxic
light-sensitive dye, the Virginia scientists were able
to sort sperm by gender with a high rate of success
Screening for Genetic
Defects with PGD
• Only specific disorders can be tested for, there is no generic test
available as a “catch-all”
• It is necessary for a disorder to be pre-identified i.e., it’s known
that parents are likely to pass on the disorder or disease to their
offspring
• Polymerase chain reaction is used on single cells to identify
disorders such as: B-Thalassaemia, Li Fraumeni syndrome, cystic
fibrosis, Duchenne muscular dystrophy (X-linked recessive trait
that weakens the muscles), and etc
http://individual.utoronto.ca/kevinkuo/GATTACA/Harper-PGD.pdf
• In brief, a polar body or a blastomere is placed in a solution that
lyses the cell and releases the DNA
• A PCR reaction mix is then added and PCR begins
The Nash Family
• Lisa and Jack Nash are carriers for Fanconi anemia, a genetic disorder
leaving them with a 1 in 4 chance of having an affected child
• They had a 6 year old daughter (Molly) who was born with a rare
genetic bone marrow disease that would kill her unless she received a
transplant from someone with an identical tissue type
• Nash’s elected 15 embryos and subject them to PGD
• A single cell was taken from each embryo and tested for genetic
mutation that causes Fanconi anemia
• They went a step further to check for which one carried a tissue type
that matched their daughter
• In August 2000, Adam Nash was born and doctors in Minnesota
performed a stem cell transplant on Molly using blood taken at birth
from Adam’s umbilical cord and his bone marrow
• Both children are healthy
Marathon Mice
• In August 2004, scientists in
California announced the birth of
“Marathon Mice”
• A new breed of geneticallymodified mice that gained muscles
and endurance without any
exercise and never became obese
• Most test subjects did not survive
due to immune responses to the
injected foreign DNA
• Therapy fails to meet rigors of
human safety, efficacy and
protection therefore not approved
for human use
ANDi
• Even though the GFP gene did
not work, it shows that for the
first time it is possible to
change the genetic make-up
of a primate by inserting a
gene into the egg
• On January 11, 2001, scientists in
Oregon unveiled ANDi (inserted DNA
spelt backwards), a baby rhesus
monkey containing a new jellyfish
gene in his genome
• The jellyfish gene green fluorescent
protein was used as it is easily
detectable under a microscope
• However, when tissue samples were
taken, they did not glow and the
green fluorescent protein was not
detectable
• "Maybe the quantity of protein is
too small to be seen or maybe the
mRNA is not being translated," says
Anthony Chan
Creating ANDi
• To create ANDi, Chan and his colleagues
injected 224 unfertilized rhesus eggs with a
virus carrying the GFP gene
• The virus's job is to integrate the gene into
a random site on one of the chromosomes
• Six hours later, each egg was artificially
fertilized by sperm injection
• Roughly half of the fertilized eggs grew
and divided, reaching the four-cell stage
• Forty were chosen and implanted into
twenty surrogate mothers—two per
mother
• Of these, three healthy males were born
and two twin males were stillborn
• ANDi was the only live monkey carrying the
GFP gene
Statistics
• In 1985, there were 30 fertility clinics in the U.S.
• Ten years later, there were more than 300
• More than one million couples seek fertility treatment
each year and spend more than 3 bill in pursuit of babies
• Fees for IVF vary between $5000 - $15,000 with another
$2-3 thousand for fertility drugs
• PGD adds several thousand dollars
• Clinic success rates improved from 17% in 1992 for women
under 40 to nearly 30% in 1999
• Success rates vary wildly from 14% to as high as 60%
Statistics
• Since 1980, according to the National Center for health statistics the
number of twins born per year has risen 67%
• The rate of triplets and higher-order birth multiples has soared from
37 per 100,000 live births in 1980 to 184 per 100 000 in 1999
• In 2001, the American Society for Reproductive Medicine
recommended transferring at most 2 embryos to the mothers
womb for younger patients while older women can recieve as many
as 5
• PGD is legal in the U.S. and Australia, but illegal in the United
Kingdom (unless used for genetic disorders), Denmark, Italy,
Portugal, Spain, New Zealand, and Germany
• Engaging in PGD or embryo selection in order to implant embryos of
a particular gender (except for the purpose of preventing,
diagnosing or treating a sex-linked disease) is a criminal act carrying
with it the penalty of up to ten years in jail and/or a $500,000 fine in
Canada
Future Outlook
• Scientists will need to do a lot more work on identifying and
isolating the specific genes that control the growth and
development of each individual feature, trait, characteristic
or talent
• They will need to work out how to alter the DNA so that the
child will match with the parent’s request
• The formation of the human is a highly complex process of
interaction & interweaving
• It is possible to imagine a society where children can be
bred for specific purposes like off planet living where
genetic manipulation is essential for survival
References
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(2002). In BIONET. Retrieved May 15, 2012, from
http://www.bionetonline.org/English/Content/db_cont1.htm
Brownlee, S. (2002, March). Designer Babies. Washington Monthly, 34(3). Retrieved
May 5, 2012, from the EBSCO database
Chan, A. W. S. et al. Transgenic monkeys produced by retroviral gene transfer into
mature oocytes. Science 291, 309-312 (January 12, 2000).
Genetic Engineering - Designer Babies. (2010). In Future Human Evolution.
Retrieved May 7, 2012, from
http://www.humansfuture.org/genetic_engineering_designer_babies.
php.htm
Lemonick, M. D. (1999, January 11). Designer Babies. Time Magazine. Retrieved May 15,
2012, from http://www.ecasd.k12.wi.us/faculty/dsampson/designer%203.pdf
Ren, Y. (2005). Designer Babies: The Pros and Cons of Genetic Engineering.
Massachusetts Institute of Technology Undergraduate Research Journal, 12, 28-32.
Retrieved May 15, 2012, from http://web.mit.edu/murj/www/v12/v12Features/v12-f4.pdf
Steinbock, B. (2008, October 11). Designer babies: choosing our children's genes. The
Lancet, 372(9646), 1294-1295. doi:10.1016/S0140-6736(08)61345-8
Picture References
• http://www.inquisitr.com/199639/ethicists-say-killing-babies-should-belegal-draw-controversy/
• http://news.bbc.co.uk/2/hi/science/nature/3592976.stm
• http://www.wired.com/science/discoveries/news/2001/01/41131
• http://homepage.smc.edu/hodson_kent/Gene_Engineering/Ethics/bone
_mar.htm
• http://www.theglobeandmail.com/life/parenting/pregnancy/pregnancytrends/the-price-of-embryo-screening/article2294658/
• http://www.scq.ubc.ca/preimplantation-genetic-diagnosis-and-ourfuture-should-we-be-peering-into-the-womb/