Thursday, December 26, 2013

Genetic Engineering of Humans – What Will Prevent It?

By Sally Painter | 12/21/13
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With the mapping of the human genome and the advancement of stem cell research, the next question to be answered is what will prevent science from altering the genetic material or DNA in humans to create super humans or designer babies? Some scientists argue that the best possible use of such research is to use it as a preventative or cure tool. Many point to the past decade of advances in this field.
Others believe that the 2001 genetic manipulation of 30 children was the beginning of what might be the point of no return with such interference in the natural order. And many scientists worry that the next step will be “designer babies” or super humans.


Types of Human Genetic Engineering

This type of HE or human cloning is the “what-if hypotheses” that science fiction books are made of.
One HGE method employs a virus-type organism that is inserted into a new gene and introduced into the human body. As a viral organism, the new gene enters human cells and replicates itself, creating an entirely new gene within the person’s genome.
The fictionalized stories of this type of science always result in nightmarish mutations. Some scientists warn while these scenarios are the extreme, they aren’t far off the mark.
Of course, it isn’t as simple as it sounds, especially when there are two choices of application for such genetic manipulation. One application is somatic. It targets specific organs and genes, yet can’t alter human eggs or sperm.
The somatic application is strictly used to address and treat existing genetic disorders. The altered gene corrects or modifies the harmful gene, but doesn’t change the patient’s actual genome. This means that the change cannot be passed on to the next or future generations. The genetic alteration is made only to the individual treated.
The other application is germline and targets human eggs and sperm. Germline can also be used to target early stage embryos. The germline application changes genes on a cellular level and alters the individual’s genome. The change will then be passed on genetically to the next generation and future generations.
Some argue that such genetic manipulation of the human genome could result in a split in the human species. It’s hypothesized that such a split could literally create a new human species that is incapable of relating, much less mating with the non-HGE humans.
In fact, some speculate that the new humans would possibly be repulsed by the original humans or unable to view them as belonging to the same species.
human dna diagram

Three Types of Human DNA Cloning

Cloning is another type of genetic engineering. The kinds of cloning that can be achieved are DNA cloning, therapeutic cloning and reproductive cloning.
When most people think of reproductive cloning they think of the famous clone sheep, Dolly and subsequent animal clones.
There are two additional types of clones. One is DNA cloning that transfers DNA to become self-replicating within foreign host cells. The second type is embryo cloning, also called therapeutic cloning. The embryo cloning is also highly controversial since it creates human embryos solely for research purposes.
First Genetically Altered Human Beings
In May 2001, the BBC reported that scientists at the Institute for Reproductive Medicine and Science of St Barnabas in New Jersey confirmed that they had performed the first genetically altered human beings before birth. 30 fetuses (15 born in America) had been created in infertile women by using genes from healthy women donors.
Two of the babies tested positive for minute quantities of additional genes that hadn’t been inherited from their parents. When tested at one year old, the children’s genetic makeup showed that they carried two mitochondria DNA. Mitochondria DNA is passed down from the mother
The DNA from the two children showed that they had two mothers. This occurrence is known as mitochondrial transfer and can also happen naturally.
The experiments were very controversial and critics warned that the additional genes could alter the children’s germline. It meant that they could possibly pass on the additional genes to their own children and future generations. In some cases, where the natural mixing of mitochondrial DNA has occurred, the double dose of maternal DNA has often caused life-threatening illnesses. This condition is known as “mitochondrial heteroplasmy”. This condition can strike the person at any stage of life.
Japanese Grow Sperm and Chinese Grow Hybrid Human Embryos from Rabbit Eggs

In 2000, Japanese scientists were successful in growing sperm in laboratories. Many researchers believe that therapeutic cloning offers a solution to infertile couples.
In September 2001, Chinese scientists at the Sun Yat-Sen University of Medical Sciences in Guangzhou inserted a boy’s DNA into “empty” rabbit eggs and grew hybrid human embryos. The purpose of the experiment was to increase the availability of transplant tissues used in therapeutic cloning since human eggs aren’t abundantly available. The cloned cells were then used to grow stem cells.
cold water immersion experiment

Dangers of Genetically Engineering Humans

Scientific ethic groups condemn this type of research and the scientific applications of HGE. Human genetic engineering still bears the stigma of the torturous inhumane experiments that Nazi doctors carried out on the Jewish people in concentration camps during World War II. As early as 1990, some countries took stances against such research, including Germany with the Embryo Protection Act.
While many European countries have passed laws against cloning that ban germline genetic engineering and reproductive cloning, it’s very difficult to stop science once the procedures have been proven possible.
The current debates over mitochondrial transfer are very similar to debates over a decade ago when the first results of DNA research were revealed. Science pursues discoveries and society attempts to control science by providing a moral conscience.
With the leaps and bounds made in medical science over the past decade the line between scientific pursuits and moral code often blur. Even self-imposed checks and balances within the scientific community can’t rein in what many feel is inevitable. Ultimately, the question remains that simply: Because it can be done, should it be done?

Image Credits:
(1) Sergiu Bacioiu via Compfight cc
(2) Wikimedia: Human DNA Diagram
(3) Wikipedia: Nazi Experiments

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