6th February, 2008!.. Discovery channel, BBC world, The Fox news and almost all media, reported about the British scientists who have done a new miracle in the biotechnological field. HUMAN embryos with three parents have been created for the first time by The British scientists. Yes. It’s true. All I can say is, the day is not too far when a child on its first day of school shares with its friends that it belongs to “one dad, and two moms”.
For as long as humans can remember, it takes one man and one woman to create a child. Many animals follow suit, with those reproducing asexually being the exceptions. Either way, two parents seem to be the natural maximum for parenting one child.
British scientists are challenging our notions of normalcy, though, as they claim to have created embryos from two women and one man: three parents. The bioethics of genetically modified babies is a touchy subject, but this group of researcher’s claims that the embryos are still primarily the result of a single man and woman.
The research was disclosed last month in parliament's upper House of Lords but has not yet been published officially in scientific journals, the university said. The impetus of this project was to help prevent the occurrence of debilitating diseases caused by mishaps in mitochondrial DNA.
I’ll be failing in my duties if I don’t tell my readers what a Mitochondria is, what happens if there is a mishap in it. Let me introduce you to “The Energisers” of the cell. “THE MITOCHONDRIA”.
MITOCHONDRIA:
Mitochondria provide the energy a cell needs to move, divide, produce secretary products, contract - in short; they are the power centers of the cell. They are about the size of bacteria but may have different shapes depending on the cell type. Mitochondria are membrane-bound organelles, and like the nucleus have a double membrane.
Mitochondria are rod-shaped organelles that can be considered the power generators of the cell, converting oxygen and nutrients into adenosine triphosphate (ATP). ATP is the chemical energy "currency" of the cell that powers the cell's metabolic activities. This process is called aerobic respiration and is the reason animals breathe oxygen. Without mitochondria (singular, mitochondrion), higher animals would likely not exist because their cells would only be able to obtain energy from anaerobic respiration (in the absence of oxygen), a process much less efficient than aerobic respiration. In fact, mitochondria enable cells to produce 15 times more ATP than they could otherwise, and complex animals, like humans, need large amounts of energy in order to survive.
Mitochondria contain their own DNA (mtDNA) which codes for 13 essential proteins that form part of the final common pathway for cellular metabolism. MtDNA is maternally inherited and each human cell contains thousands of copies. Patients with pathogenic mutations of mtDNA often harbour a mixture of mutated and wild-type genomes (heteroplasmy). The clinical phenotype is related to the proportion of mutated mtDNA inherited from the mother, and this can vary markedly, both between siblings and also within the same individual.
MITOCHONDRIAL DISEASES:
More than 40 known types
Mitochondrial disease is a difficult disorder to identify because it can take many forms, and range from mild to severe. The problems it causes may begin at birth or not occur until later in adult life. It is estimated that mitochondrial disease affects between 40,000 and 70,000 Americans, occurring in one in 2,500 to 4,000 births.
Mitochondria may not function correctly due to a genetic defect, damage caused by drugs, or damage caused by free radicals (destructive molecules).
Many effects, many symptoms: -
Because mitochondria are in cells all over the body, many different organs may be affected, including the brain and muscles. Some of the problems associated with mitochondrial disease are:
- Brain: developmental delays, mental retardation, seizures, dementia
- Nerves: weakness, pain
- Muscles: weakness, low tone, cramping, pain
- Heart disease
- Eyes: twitching, vision loss
- Kidney disease
- Respiratory problems
Treatment
There is no cure for mitochondrial disease. Some helpful treatments include vitamins such as thiamine (B1), riboflavin (B12), vitamin C, and vitamin E. Lipoic acid and coenzyme Q-10 are also useful supplements.
Some researchers are examining using drugs to block lactic acid buildup in the body that is common in mitochondrial disease. Others are trying very low carbohydrate diets to reduce the workload for mitochondria.
But here is a latest technique, a complete cure, and one day, may completely eradicate the diseases from the world. But how is it done?!
MECHANISM: -
It sounds like the storyline from a cheesy film, but a human embryo has been created using the genetic material from one man and two women. A team from Newcastle University, England, developed the technique in the hope that it could be used to prevent diseases caused by faulty mitochondria. Their experiment started with two ingredients: first, a left over (and 'severely abnormal') embryo from an IVF treatment; second, a donor egg from another woman. The donor egg has all but the mitochondrial DNA removed, and then a nucleus from the embryo is inserted into the egg. Effectively, this results in a mitochondria transplant. The protocol may sound quite simple, but a very risky and a superbly elegant one. 'While any baby born through this method would have genetic elements from three people, the nuclear DNA that influences appearance and other characteristics would not come from the woman providing the donor egg. However, the team only has permission to carry out the lab experiments and as yet this would not be allowed to be offered as a treatment.
ETHICAL ISSUES…..
Critics argue the research is a worrying step towards creating genetically manipulated or "designer" babies. The y say going against nature will ruin the concept of family unit.
Mitochondrial DNA is not part of the genome that is contained in the cell nucleus. It isn't even genetic material the cell directly governs. Mitochondria are actually capable of replicating their own genomes and dividing without influence of the cell itself. (I.e. they replicate independently of mitosis). So there is no way that a “mitochondrial transplant violates” any kind of ethics or any religious issues. This topic is simply fascinating…
All new inventions in science will have to face such issues. When the world did not accept the concept of “earth revolving around sun” given by Galileo, how will the world accept this concept?! For years people believed that the Drosophilas take birth from the fruit flies itself, until it was disproved by An Italian priest, Lazzaro Spallanzani’. Nobody accepted the idea of invitro fertilization itself at first, but now?! Now, it’s a boon to those who do not have children. Everybody raised their voice against surrogate motherhood. But now, the government is thinking of legalizing it. It’s all a matter of few days. Society will accept it soon, and it has to.
“We are not trying to alter genes, we're just trying to swap a small proportion of the bad ones for some good ones," said Patrick Chinnery, a professor of neurogenetics at Newcastle University involved in the research.
Dr.Patrick Chinery, Brain behind the Magic
"Most of the genes that make you who you are; are inside the nucleus," Chinnery said. "We're not going anywhere near that."
Prof.Doug Turnbull.
“Maybe in five to ten years we will be able to do something to stop the inheritance of Mitochondrial diseases”, said Dr. Turnbull, The head of the team.
So far, 10 such embryos have been created, though they have not been allowed to develop for more than five days. Chinnery hoped that after further experiments in the next few years the process might be available to parents undergoing in-vitro fertilization.
The science still has a long way to go…………
For further info, visit...
news.softpedia.com/news/
blog.wired.com/wiredscience/
