Wednesday, 4 April 2012

human-animal hybrid embryos

Human-animal hybrid embryo                                                 
What is hybrid?
Anything that is derived from heterogeneous sources, or composed of elements of different kinds.
Example: hybrid vehicles that generate power via fuel and electric.

What is a hybrid embryo?
A mixture of both human and animal tissues.


“True chimeras”: addition of a cell from an animal embryo to a human embryo producing either wholly human or wholly animal.
“Transgenic human embryos”: genetically altered human embryos that contain a small amount of animal DNA.
“True hybrid”: fertilization of a human egg by an animal sperm or vice versa resulting in 50% human and 50% animal DNA.
(BBC  News 2008)

How a human-animal hybrid embryo is produced?
Graphic showing the sequence for the cytoplasmic method of creating hybrid embryos from animal and human tissue
(BBC News 2008)
First human-animal hybrid embryo was produced in British by Lyle Armstrong and the team at Newcastle University. They inserted human DNA from a skin cell into a cow egg.
(The Guardian 2008)

Is human-animal hybrid embryo a reward ???
*      Medical-based research
Researchers may conduct scientific experiments using cells developed from human-animal hybrid embryos to identify the roots that cause complex diseases and impacts that might have on human body. Ways to reduce the effects or treat a disease could also me discovered.
Examples: Parkinson’s, Alzheimer’s and motor neuron diseases

*      Cell or tissue transplant
Stem cells produced from human-animal hybrid embryos to replace worn-out/dead cells.
Example: skin grafting
A victim of a fire having severe injury on the skin (large skin surface burnt) may have a chance to receive treatment of epithelial tissue transplant in a short time.

*      Organ transplant
Stem cells derived from human-animal hybrid embryos into a functioning organ.
Cells à tissuesà organà systemà organism
Example: liver and kidney
Critical patients would have to wait for a long period in order to get a liver from a donor which is matching. With the advancement of human-animal hybrid embryo, a genetically identical liver could be cloned using active genes from the patient.

*      Savior siblings
A “designed” child with desired genes can be created to save an existing sick sibling.
Example: leukemia
A child suffering from leukemia may accept stem cells from umbilical cord or bone marrow of the newly-born child.

Or a disaster ???!!!
*      Unethical
“A monstrous attack on human right, human dignity and human life”. (O'Brien 2007)
It is immoral to surimpose animal embryos in the womb or bring them to term.
It might destruct human life as they tamper with the nature.

Will the scientists be able to continue their work?
Two licences to create one type of hybrid embryo have already been granted by the Human Fertilisation and Embryology Authority.
(BBC News 2008)

Brain activity
Why must the nucleus be injected into an egg cell? Why can’t it be injected into other somatic cells such as muscle cells and skin cells?
Answer: Muscle cells and skin cells undergo differentiation and specialisation. They can only conduct specific functions. (ie. Muscle cells can only divide into muscle cells.) Egg cells can divide into cells that have different gene turned on/ activated as they consist of universal DNA from parental cells.

References and Bibliography 
Embryology Bill: The key points 2008, viewed 15 March 2012, <>

First British human-animal hybrid embryos created by scientists 2008, viewed 15 March 2012, <>

Lauder, S 2011, Stem cell laws rule out hybrid embryo, 8 July, ABC news, viewed 15 March 2012, <>

Martin, D and Caldwell, S 2011, 150 human animal hybrids grown in UK labs: Embryos have been produced secretively for the past three years, 22 July 2011, Daily Mail, UK, viewed 15 March 2012, <>

Q & A: Hybrid Embryos 2008, viewed 15 March 2012, <>
Viewed 15 March 2012, <>

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