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Prof Gerald Schatten
University of Pittsburgh, USA
Welcome to The Brave New World of ART:
Genetic Modifications, Manufactured Gametes
and Exotic Inheritance
Nothing to declare
Dr. Min Chueh Chang; 张明觉; 張明覺; October 10, 1908 – June 5, 1991
Dr. Min Chueh Chang (simplified Chinese: 张明觉; traditional Chinese: 張明覺; pinyin: Zhāng Míngjué, October 10, 1908 – June 5, 1991), often credited as M.C. Chang, was a Chinese-born American reproductive biologist. His specific area of study was the fertilisation process in mammalian reproduction. Though his career produced findings that are important and valuable to many areas in the field of fertilisation, including his work on in vitro fertilisation which led to the first "test tube baby", he was best known to the world for his contribution to the development of the combined oral contraceptive pill at the Worcester Foundation for Experimental Biology.
14 APRIL 2017 • VOL 356 ISSUE 6334 137 SCIENCE sciencemag.org
By Martin Pera
tem cells, grown under the right
conditions in vitro, have a remark-
able ability to undergo differentiation
and self-assembly into complex, three-
dimensional organoids, similar in ana-
S tomical and functional organization to
the developing brain, kidney, gut and other
tissues (1). On page 153 of this issue, Harrison et al. (2) show that when mouse embryonic
stem cells are cultured together with tro-
phoblast stem cells (which give rise to part of
the placenta), the resulting constructs
develop into structures that bear a striking
resemblance to the mouse embryo after it
has implanted into the womb. The finding
raises the possibility that by using advanced
cell culture techniques, including coculture
of multiple cell types, and engineering the
appropriate culture microenvironment, it
might be possible to model human embryo-
genesis in a petri dish.
STEM CELLS
The Jackson Laboratory, Bar Harbor, ME, USA.
Email: [email protected]
“... it might be possible to model human embryogenesis in a petri dish .”
Human embryo culture and embryonic
stem cell culture have opened up a previ-
ously inaccessible phase of the human life
cycle to experimental study. Until recently, in
vitro growth of mouse or human embryos
has mainly been limited to cultures that
reach the blastocyst stage, or the equivalent
of about 5 or 6 days of embryonic develop-
ment. Many of the most important events in
embryogenesis, including those involved in
developmental disorders, occur in a critical
interval shortly after this stage. In 2016, the
culture of human embryos was extended out
to 13 days of development, a point at which
many of the key structures that will sup-
port the growth of the embryo have formed.
At this stage, the embryo is preparing to
Published by AAAS
Embryogenesis in a dish We are at an early stage of developing embryos from stem cells in culture
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C H IN A ’ S P U S H
etting time with Qiao Jie is not easy. At
7:30 a.m., the line coming outof the fertility
centre that she runs blocks the doorway
and extends some 80 metres down the
street. Inside, about 50 physicians on her Gteam are discussing recent findings, but
Qiao, a fertility specialist andpresidentof Peking
University Third Hospital in Beijing, is still in an early-morning consult.
When she finally emerges, she jumps to the topic at hand: spreading awareness of preimplantation genetic diagnosis (PGD), a procedure that helps couples undergoing in vitro fertilization (IVF) to avoid passing on genetic mutations that could cause disease or disability in their children. Qiao typically refuses interview requests, but she’s concerned that people aren’t getting the message about PGD fast enough. “Now, more and more dis- eases can be stopped — if not immediately, in the generation after next,” she says.
Early experiments are beginning to show how genome-editing technologies such as CRISPR might one day fix disease-causing mutations before embryos are implanted. But refining the techniques and getting regulatory approval will
take years. PGD has already helped thousands of couples. And whereas the expansion of PGD around the world has generally been slow, in China, it is starting to explode.
The conditions there are ripe: genetic diseases carry heavy stigma, people with disabilities get very little support and religious and ethical push-back against PGD is almost non-exist- ent. China has also lifted some restrictions on family size and seen a subsequent rise in fer- tility treatments among older couples. Genetic screening during pregnancy for chromosomal abnormalities linked to maternal age has taken off throughout the country, and many see this as a precursor to wider adoption of PGD.
Although Chinese fertility doctors were late to the game in adopting the procedure, they have been pursuing a more aggressive, com- prehensive and systematic path towards its use
there than anywhere else. The country’s central government, known for its long-term thinking, has over the past decade stepped up efforts to bring high-quality health care to the people, and its current 5-year plan has made reproductive medicine, including PGD, a priority, an effort that Qiao is leading. Researchers are hunting
down various mutations in the Chinese popu- lation that might be screened for in PGD. And well-equipped and powerful clinical-research groups, including Qiao’s, are stepping up efforts to improve the technology, increase awareness and bring down costs.
Comprehensive figures are difficult to come by, but estimates from leading PGD providers show that China’s use of the technique already outpaces that in the United States, and it is grow- ing up to five times faster. Qiao’s clinic alone now performs more procedures with PGD each year than all of the United Kingdom.
“Looking over the development in China over the past 10 years, they might start to think it’s possible to get rid of these diseases,” says Kangpu Xu, a Chinese-born reproductive biologist at Weill Cornell Medical College in New York City.
Such systematic efforts raise thorny questions forbioethicists. Some worry thatpushes to elim- inate disabilities devalue the lives of those who already have them. The cost and accessibility of the procedure raises concerns about genetic traits further widening the divide between rich and poorpeople. Thenthere are concerns about
BY DAVID CYRANOSKI
RO
PI/
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MA
F O R
B E T T E R B A B I E S A campaign to increase preimplantation genetic diagnosis could put the country on the path towards eliminating certain diseases.
2 7 2 | N A T U R E | V O L 5 4 8 | 1 7 A U G U S T 2 0 1 7
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Four experimental routes for nuclear reprogramming J. B. Gurdon et al., Science 322, 1811 -1815 (2008)
al-kimiaالكيمياء
A damaged heart.
A Rosenzweig Science 2012;338:1549-1550
Published by AAAS
5/30/2017 In ‘Enormous Success,’ Scientists Tie 52 Genes to Human Intelligence The New York Times
https://nyti.ms/2qMIzrI
SCIENCE
In ‘Enormous Success,’ Scientists Tie 52 Genes to Human Intelligence Carl Zimmer
MATTER MAY 22, 2017
In a significant advance in the study of mental ability, a team of European and American scientists announced on
Monday that they had identified 52 genes linked to intelligence in nearly 80,000 people.
These genes do not determine intelligence, however. Their combined influence is minuscule, the researchers
said, suggesting that thousands more are likely to be involved and still await discovery. Just as important, intelligence
is profoundly shaped by the environment.
Still, the findings could make it possible to begin new experiments into the biological basis of reasoning and
problemsolving, experts said. They could even help researchers determine which interventions would be most
effective for children struggling to learn.
One particularly controversial application of this powerful gene editing technology is the possibility of driving certain species to extinction – such as the most lethal animal on Earth, the malaria-causing Anopheles gambiae mosquito. This is, as far as scientists can tell, actually possible, and some serious players like the Bill and Melinda Gates Foundation are already investing in the project. (The BMGF funds The Conversation Africa.)
Yang’s genetically modified mushrooms were deemed exempt from current USDA regulation.
Gerald Schatten
Oregon Regional Primate Research Center and Oregon Health Sciences University
Portland OR, USA
Phenotypic characterization of OCT4-targeted human embryos
N M E Fogarty et al. Nature 1–7 (2017) doi:10.1038/nature24033
Juan Carlos Izpisua Belmonte, Edward M. Callaway, Sarah J. Caddick, Patricia Churchland, Guoping Feng, Gregg E. Homanics,
Kuo-Fen Lee, David A. Leopold, Cory T. Miller, Jude F. Mitchell, Shoukhrat Mitalipov, Alysson R. Moutri...
Brains, Genes, and Primates
null, Volume 86, Issue 3, 2015, 617–631
http://dx.doi.org/10.1016/j.neuron.2015.03.021
