2013 marek vácha. cloning plants f.c. steward in cornell university in 1950s

2013Marek Vácha

Cloning Plants

F.C. Steward in Cornell University in 1950s

Totipotention: plants

Hans Driesch, 1892

Hans Spemann, 1918

Robert Briggs and Thomas King, 1950s1952

"renucleated cell"

Rana pipiens

Briggs and King

Something does change as animal cells differentiate...

John Gurdon, 1975

Journal of Embryology and Experimental Morphology 34:93-112 (1975)

When nuclei came from the fully differentiated intestinal cells of a tadpole, fewer than 2% of the eggs developed into normal tadpoles

Xenopus levis

2012: John Gurdon wins Nobel Prize

(1933 - )

classic experiment has been published in 1962

"I believe Gurdon has ideas about becoming a scientist. In present showing, this is quite ridiculous."

Gurdon´s teacher of biology

Xenopus is evolutionary more primitive frog than Rana pipiens

Gurdon, too, found a progressive loss of potency with increasing developmental age, although Xenopus cells retained their potencies for a longer period than did the cells of Rana.

In the Briggs and King experiments, transplanted nuclei from larval cells produced adults, while Gurdon´s work showed that that transplanted adult nuclei could produce larvae.

Reproductive Cloningthe Ian Wilmut team created Dolly the Sheep in 1996

A total of 430 eggs were surgically removed from ewes. Each egg was then stripped of its DNA and filled with the udder cell.

The egg and the cell were then fused with an electric current.

To get Dolly, the Scottish scientists transferred 277 adult nuclei into sheep eggs, implanted 29 clonal embryos, and achieved the birth of only one live lamb clone

Keith Campbell (1954 - October 5 2012

Keith Campbell (left) with Dolly, Fay Weldon (a journalist), and Ian Wilmut

Keith Campbell (1954 - 2012)

people are shaped by environment as well as genetics. “If you had 40 Adolf Hitlers that had been

cloned, they’d probably be nice guys,”

Wilmut: Campbell deserved “66 per cent” of the credit for Dolly.

15/07/1996 - 14/02/2003

Dolly the Sheep

Dolly was born after 276 failures

CC

CC = Carbon Copy first cloned cat, CC,

has a calico coat, like her single female parent, but the color and pattern are different because of random X chromosome inactivation, which is normal occurence during embryonic development

(Reece, J.B., Urry, L.A., (2011) Campbell Biology. 9th. ed. Pearson Publication, Inc. , New York. p. 460)

In a herd of cows cloned from the same line of cultured cells, certain cows are dominant in behavior and others are more submissive.

(Reece, J.B., Urry, L.A., (2011) Campbell Biology. 9th. ed. Pearson Publication, Inc. , New York. p. 457)

COMPACTION

Shortly after formation of 8 cells (around four days after fertilization), the blastomeres remain loosely connected to one another

Soon afterward, they huddle together, maximizing their contact with one another and forming a compact balls of cells

COMPACTION

This tighly packed arrangement is stabilized by tight junctions that form between the outside cells of the ball, sealing off the inside of the sphere

the cells of the compacted embryo divide to produce a 16-cell morula

(Gilbert, S.C., Tyler, A.L., Zackin, E.J., (2005) Bioethics and the New Embryology. Sinauer Associates, Inc. W.H. Freeman & comp. Sunderland, MA U.S.A. p. 14)

MORULA

consists of a small group of internal cells surrounded by a larger group of external cells descendantsof the exterior cells become

trophoblast cells trophoblast cells form tissue of the chorion, the

embryonic portion of the placenta inner cells generate inner cell mass (ICM)

ICM will give rise to the embryo and its associates yolk sac, allantois and amnion

Reproductive and Therapeutic Cloning

Therapeutic cloning: humans

May 2013. Dr. Shoukhrat Mitalipov method could generate heart, liver and nerve

cells from high-quality egg cells.

Donor egg cytoplasm containing skin cell nucleus

Early stage human SCNT embryos - day 2

Egg donors for the experiment received US$3,000–7,000 in compensation. This is expensive and, according to some bioethicists, risks creating an organ trade that preys on the poor. Because the technique requires the destruction of embryos, funds from the US National Institutes of Health (NIH) cannot be used to make or study SCNT-derived cell lines, hampering further clinical research.

http://www.nature.com/news/human-stem-cells-created-by-cloning-1.12983

http://www.nature.com/news/human-stem-cells-created-by-cloning-1.12983

Defense of cloning research

The last year the luminaries of the International Academy of Humanism—including biologists Crick, Dawkins, and Wilson and humanists Isaiah Berlin, W. V. Quine, and Kurt Vonnegut—issued a statement in defense of cloning research in higher mammals and humans beings. Their reasons are revealing:

What moral issues would human cloning raise? Some world religions teach that human beings are fundamentally different from other mammals . . . . Human nature is held to be unique and sacred. Scientific advances which pose a perceived risk of altering this “nature” are angrily opposed. . . . [But] [a]s far as the scientific enterprise can

determine . . . [h]uman capabilities appear to differ in degree, not in kind, from those found among the higher animals. Humanity’s rich repertoire of thoughts, feelings, aspirations, and hopes seems to arise from electrochemical brain processes, not from an immaterial soul that operates in ways no instrument can discover. . . . Views of human nature rooted in humanity’s tribal past ought not to be our primary criterion for making moral decisions about cloning. . . . The potential benefits of cloning may be so immense that it would be a tragedy if ancient theological scruples should lead to a Luddite rejection of cloning. (International Academy of Humanism, 1997.)

Reproductive Cloning

1996 sheep 1997 mouse 1998 cow 2000 pig 2002 cat 2005 dog 2009 camel

Capra pyrenaica „bucardo“

officially declared extinct in 2000 when the last-known animal of its kind was found dead in northern Spain

The karyoplasts were thawed fibroblasts derived from skin biopsies, obtained and cryopreserved in 1999 from the last living specimen, a female, which died in 2000.http://www.ncbi.nlm.nih.gov/pubmed/19167744

2007: first primate (macaque) embryos were cloned by researches at the Oregon National Priate Center clones reached blastocyst stage (Reece, J.B., Urry, L.A., (2011) Campbell Biology. 9th. ed. Pearson Publication, Inc. , New

York. p. 461)

Problems Associated with Animal Cloning

cloned mice are prone to obesity, pneumonia, liver failure, and premature death

even cloned animals that appear normal are likely to have subtle deffects.

Reasons: regulation of gene expression is often the result of

epigenetic changes in chromatin, such as acetylation of histones or methylation of DNA

DNA from cloned embryos often has more methyl groups than does the DNA in equivalnt cells from normal embryos of the same species.

reprogramming of donor nuclei requires chromatin restructuring, which occurs incompletly during cloning procedures

cloned animals have also be re-cloned, and clones have reproduced sexually, although many cloned males are sterile (the earliest succesful clones were all female)

K.C., a cow cloned at the University of Georgia from the cell af a dead cow, gave birth in December 2004 to Sunshine, a calf who seems normal in every way

(Pierce, J., Randels, G., (2010) Contemporary Bioethics. Oxford University Press, NY, Oxford. p. 260)

Mammoth cloning?

The process will involve putting DNA from the mammoth into an Asian elephant's egg that has been stripped of elephant genes.

It would start with DNA from a cell frozen by nature The chances of DNA being completely intact is

very small. Even if intact DNA were available, trying to clone it

in an Asian elephant, a species from which mammoths diverged some five million years ago, would be ''the equivalent of crossing a human with a chimpanzee.''

http://www.nytimes.com/1999/10/29/us/cloning-of-mammoth-is-unlikely-an-expert-says.html

the mammoth’s genes differ at some 400,000 sites on its genome from that of the African elephant. “That’s not making a mammoth. It’s

‘mammothifying’ an elephant.”

Mammoth Genome Project: http://mammoth.psu.edu/

Cloning Neanderthals?

...or Denisovans? If the mammoth can be resurrected, the

same would be technically possible for Neanderthals.

Declarations, Treaties, Law etc.

Oviedo Treaty

Additional Protocol to the Convention for the Protection of

Human Rights and Dignity of the Human Being with regard to the Application of Biology and Medicine, on the Prohibition of Cloning Human Beings

Additional Protocol, 1998

Article 1 1 Any intervention seeking to create a

human being genetically identical to another human being, whether living or dead, is prohibited.

2 For the purpose of this article, the term human being “genetically identical” to another human being means a human being sharing with another the same nuclear gene set.

Explanatory report to the Additional Protocol to the Convention on Human Rights and Biomedicine on the Prohibition of Cloning Human Beings

3. Deliberately cloning humans is a threat to human identity, as it would give up the indispensable protection against the predetermination of the human genetic constitution by a third party. Further ethical reasoning for a prohibition to clone human beings is based first and foremost on human dignity which is endangered by instrumentalisation through artificial human cloning.

Explanatory report to the Additional Protocol to the Convention on Human Rights and Biomedicine on the Prohibition of Cloning Human Beings

Even if in the future, in theory, a situation could be conceived, which might seem to exclude the instrumentalisation of artificially cloned human offspring, this is not considered a sufficient ethical justification for the cloning of human beings. As naturally occurring genetic recombination is likely to create more freedom for the human being than a predetermined genetic make up, it is in the interest of all persons to keep the essentially random nature of the composition of their own genes

UNESCO: Universal Declaration on the Human Genome and Human Rights11 November 1997

nonbinding Universal Declaration on the Human Genome and Human Rights

UNESCO: Universal Declaration on the Human Genome and Human Rights11 November 1997

Article 11

Practices which are contrary to human dignity, such as reproductive cloning of human beings, shall not be permitted. States and competent international organizations are invited to co-operate in identifying such practices and in taking, at national or international level, the measures necessary to ensure that the principles set out in this Declaration are respected.

Defense of cloning research

The last year the luminaries of the International Academy of Humanism—including biologists Crick, Dawkins, and Wilson and humanists Isaiah Berlin, W. V. Quine, and Kurt Vonnegut—issued a statement in defense of cloning research in higher mammals and humans beings. Their reasons are revealing:

What moral issues would human cloning raise? Some world religions teach that human beings are fundamentally different from other mammals . . . . Human nature is held to be unique and sacred. Scientific advances which pose a perceived risk of altering this “nature” are angrily opposed. . . . [But] [a]s far as the scientific enterprise can

determine . . . [h]uman capabilities appear to differ in degree, not in kind, from those found among the higher animals. Humanity’s rich repertoire of thoughts, feelings, aspirations, and hopes seems to arise from electrochemical brain processes, not from an immaterial soul that operates in ways no instrument can discover. . . . Views of human nature rooted in humanity’s tribal past ought not to be our primary criterion for making moral decisions about cloning. . . . The potential benefits of cloning may be so immense that it would be a tragedy if ancient theological scruples should lead to a Luddite rejection of cloning. (International Academy of Humanism, 1997.)

Arguments for reproductive cloning if a woman had a serious mitochondrial

disorder, she could become pregnant with a donated oocyte (which would supplied the mitochondria) into which a nucleus of one of her or her partner´s somatic cells had been transplanted

Arguments for reproductive cloning

To allow an infertile couple to have a child

To bring back a child killed in an accidentIn recent years, some bereaved families have contacted scientists asking them to clone a dead child.

To replicate the talents of exceptional human beings

Out of curiosity or to attempt some sort of immortality The scientist Richard Dawkins has expressed the desire to clone himself out of pure curiosity.

Arguments against reproductive cloning cloned humans may face problems of identity and

individuality because they are genetically identical to people who already

lived, and there may be expectations to be like their predecessors

cloning could contribute to the commodification of children and the commercialization of reproduction

cloning could lead to eugenics, favoring particular genetic traits

family relations might be confused, such as if the father and son were genetic twins, this also "brothers"

there might be a slippery slope impact on society, leading to such things as genetic enhancement and genetic control over the next generation

Arguments against reproductive cloning argument of "an open future"

by choosing a child´s genetic makeup in advance, parents deny the child´s right to an open future

Arguments against reproductive cloning it is ironic that those who believe that you

can´t stop science, present themselves as wise to the ways of the world, yet understand so little of how science really works. It is they, not those who believe cloning can be banned, who are the naïve idealists

(King, D., (2003) Cloning? Yuk! In: Key Issues in Bioethics. (eds) Levinson, R., and Reiss, M.J., London, RotledgeFalmer, pp. 59-68)

Arguments against reproductive cloning As Harvard philosopher Hilary Putnam put

it: "Every child has the right to be a complete surprise to its parents"

Jewish perspective: the glory of creation is that unity in heaven creates diversity on earth.

Sacks, J., (2009) Genesis: The Book of Beginnings. Covenant and Coversation. Maggid Books and The Orthodox Union. New Milford, USA, London, Jerusalem. p. 150

Arguments against reproductive cloning cloning is a radical form of child abuse Asexual reproduction, which produces

"single parent" offspring, is indeed a radical departure from the natural human way, confounding all normal understandings of father, mother, sibling, grandparent and the like, and all oral relations tied thereto.

(Kass, R.L., (2002) Life, Liberty and Defense of Dignity. Encounter Books, New York, London. p. 150,154)

Arguments against reproductive cloning cloning threatens confusion of identity and and

individulality, even in small-scale practice cloning represents a giant step toward transforming

procreation into manufacture, that is, toward the increasing depersonalization of the process of generation and toward the "production" of human children as articfacts, products of human will and design

cloning - like other forms of eugenic engineering of the next generation - represents a form of despotism of the cloners over the cloned, and thus a blatant violation of the inner meaning of parent-child relations, of what it means to have a child, of what it means to say "yes" to our own demise and "replacement"


Argumenty proti reprodukčnímu klonování cloning is a radical form of child abuse Asexual reproduction, which produces

"single parent" offspring, is indeed a radical departure from the natural human way, confounding all normal understandings of father, mother, sibling, grandparent and the like, and all oral relations tied thereto.


Arguments against reproductive cloning Can anyone really give an argument

fully adequate to the horror that is father-daughter incest (even with consent)(...) or the eating of human flesh? (...) Would anybody´s failure to give full rational justificatin for his revulsion at those practices make that revulsion ethically suspect? Not at all.


Arguments against reproductive cloning the power of sexuality is rooted in its strange

connection to mortality, which it simultaneously accepts and tries to overcome. Asexual reproduction may be seen as a continuation of the activity of self-preservation.

(Kass, R.L., (2002) Life, Liberty and Defense of Dignity. Encounter Books, New York, London. p. 150)

in all higher animals, reproduction as such implies both the acceptance of the death of self and participation in its transcendence. The salmon, willingly swimming upstream to spawn and die, makes vivid this universal truth.

Arguments against reproductive cloning No family dynamic is likely to be

unaffected by the fact that the cloned child will have a special relationship to only one of his or her parents. And what will hapen when the adolescent clone of Mommy becomes the spitting image of the woman with whom Daddy once fell in love? In case of divorce, will Mommy still love the clone of Daddy, even though she can no longer stand the sight of Daddy himself?


Arguments against reproductive cloning Whereas most parents normally have

hopes for their children, cloning parents will have expectations, indeed, will likely have a plan. The child is given a genotype that has already lived, with full expectation that this blueprint child now means a child who exists precisely to fulfill parental wants.


2013 marek vácha. cloning plants f.c. steward in cornell university in 1950s

Documents