Mitochondrial Clock:The story of Mitochondrial Eve

Does our mitochondrial DNA show that all humans come from the same mother? So, did this mitochondrial Eve live 200,000 years ago, or at the calculated value of 6500 years ago? Some parts of the mitochondrial DNA are expected to change much faster than expected, but there is a lot of opposition to this possibility because it opposes the speed of the calculated molecular clock based on separation of chimpanzees and humans 5 million years ago.

 


  1. Generally

Does our mitochondrial DNA show that all humans come from the same mother? So, did this mitochondrial Eve live 200,000 years ago, or at the calculated value of 6500 years ago? Some parts of the mitochondrial DNA are expected to change much faster than expected, but there is a lot of opposition to this possibility because it opposes the speed of the calculated molecular clock based on separation of chimpanzees and humans 5 million years ago.

The FBI has also been introduced by setting new rules for mtDNA to add a faster rate of mutation to the account. Panik, Air decided that these new mtDNA data do not agree with the rate of established evolutionary change. A letter from the editor (listed below): “mtDNA mutation rates-no panic”, indicates the current climate. The “International Workshop on the First Mitochondrial DNA” was organized in 1997 to investigate the problems of mtDNA mutation rates.

Ann Gibbons noted that the workshop, as they have seen, made a very interesting introduction to the problems: “Mitochondrial Saitin Calibrating”: Science Volume 279, Issue 5347, 2 January 1998, pp. 28-29. Summary for Ann Gibbons’s article: “Mitochondrial DNA changes much faster than expected, launches new DNA forensic procedures, and problematic questions arise about the dating of evolutionary events.”

  • Structure

Introduction to the story of mitochondrial Eve. Is it true that the scientist understands all of us? There are two opposite points of view in human history. While the story of the mitochondrial Eve supports the “out of Africa” perspective, those with the “multi-zone continuity” theory continue to draw attention to the problems in Eve research.

 

Is the mitochondrial clock speed faster than we thought? Some have estimated that “mitochondrial Eve” probably lived 100,000 to 200,000 years ago in Africa. However, it has been found that mtDNA can experience a much faster rate of mutation. Using this faster rate of mutation as a new clock speed, Eve can be calculated to live only 6500 or 6000 years ago.

 


  • Section

Continuation of the story of the mitochondrial Eve. Is the clock speed faster than we thought? Is the idea of maternal mitochondrial inheritance correct? Or is it convincing evidence for recombination and paternal inheritance of mitochondrial DNA? How reliable is the sperm mitochondrial translocator in sperm destroying mitochondrial DNA and maintaining maternal inheritance of mtDNA ?

 

Is there a Creationist model that would allow mitochondrial Eve and mitochondrial clock data to conform to “multi-domain continuity” data involving Homo erectus

 

     


      Illustrations

Mitochondrial Eve

In 1987, Cann, Stoneking and Wilson published a world-wide research on human mitochondrial DNA (mtDNA) in Nature. The main point was

that “all mitochondrial DNAs originated from a woman” and probably lived in Africa 200,000 years ago. When the media picked up Wilson, one of the authors of the article he found the “Mitochondrial Eve” or “African Waves”, the story was a feeling. Did the scientists find “all of us mother”?

 

Most people know the nuclei of the cells and the genetic inheritance of both parents is in the nucleus. People have both 46 chromosomes, as well as their parents. The fragments of DNA taken from both the mother and the father are brought together in a recombination process that allows them to have features from both their mothers and their fathers.

 

However, there are DNA in other parts of the cell. In the cytoplasm, organelles called mitochondria, which provide energy for the cell in the form of ATP, also have DNA. However, it is not seen that this DNA came from both parents. Instead, it seems that there are only exceptional exceptions from the mother and from the Father (except that your mother is contributing to the mitochondrial DNA, see the Mitochondrial Hour Update: Is the maternal mitochondrial heritage still considered correct?).

 

Initially, the majority of people in sperm were thought to be out of the egg. It was thought that only the nuclear DNA and the centrosome of the head had entered the egg. But that changed. It has now been determined that all sperm have entered the egg. However, almost all sperm are broken down by enzymes. Chromosomes found only in crystal form in the sperm head are conserved and used in the recombination process to produce the final version of the new egg cell DNA. The sperm mitochondria and its DNA are cleaved by enzymes made for this purpose. See the Mitochondrial Clock Update for details. However, the result is still the same. Mitochondria and its sperm DNA are not used. Mitochondria are only used for eggs for the developing person.

 

I mean, our mitochondrial DNA is basically like your mother’s. Mitochondrial DNA is transmitted from mother to daughter, from generation to generation. The mitochondrial DNA she gets from her mother is a dead end for the mitochondrial DNA not to be used in children.

 

Nuclear DNA varies greatly as it undergoes recombination in each generation. However, mitochondrial DNA is transferred from generation to generation without any recombination. The normal rate of mutation that occurs only when the DNA is copied allows the mitochondrial DNA to change. That’s why the worldwide survey can determine that all people are associated with an original mother they call “mitochondrial Eve.” Ancestor trees are produced that depend on the slow mutation rate of mitochondrial DNA to predict how the whole human population came from a single woman.

 

After the first discovery of the “Mitochondrial Eve”, Wilson was uncomfortable with the term “Eve” because he began to think that many people were the only women who lived at that time, just as it was written in the Creation of the Sacred Book about Adam. and Eve in the Garden of Eden. Moreover, the usual evolutionary time scale for human beings did not allow for as little as 200,000 years. More importantly, it is believed that a person is around for a longer period of time. Java people are thought to be 800,000 years old. Homo erectus specimens are found all over the world. More than 40 Asian Homo erectus specimens from China were between 220,000 and 500,000 years old. It is believed that the earliest remains of Lucy and the first specimens he has been standing for are at least 1 to 4 million years.

 

Hence, if the human being is thought to be in existence for a time longer than just 200,000 years, it has come to the conclusion that mitochondrial Eve should not be the first human female, nor should it be the only female to survive. time. Evolutionists have begun to believe that Eve must be one of the many women of its time in a genetic bottleneck. It’s a time when you have a small living population.

 

It is not known why the human population is so exhausted in a bottleneck. Some argue that environmental pressures can drag people’s population to near extinction. It has even been suggested that the ability to speak languages ​​is only one reason why only one group survives all of the others. There are all sorts of reasons to explain why bottlenecks exist: a constant record, asteroid effect, or climate change are just a few of many.

 

Many people claim that Eve must have a tremendous advantage because it is thought that the offspring conquered the whole world without conquering the whole world.

 

Many suggest that Eve must have had some vast superiority because her offspring are thought to have conquered the whole world without any evidence of any interbreeding. Others state that selection had nothing to do with the takeover of the human population. They inject that it was a purely statistical process.

 


Equations

Mitochondrial Clock

Is clock speed faster than we thought?

 

The 200,000-year-old time scale in which Eve lived was calculated using the idea that the common ancestors of chimpanzees and humans lived 5 million years ago, and that both nuclear DNA and mitochondrial DNA changed in a constant manner.

 

What this means is that the variation in the sample of human mitochondrial DNA from different groups of humans in the world is compared to the differences found by comparing mitochondrial DNA of human and chimpanzee. It is done with proportion. When we think that humans and chimpanzees are separated from each other, how many genetic changes have been made since 5,000,000 years, we can calculate how long it will take for a few genetic changes that we have in the human mitochondrial DNA to be produced.

 

For one example; There are 65 differences in the genetic code between a particular mitochondrial gland, human and chimpanzee, but there are about 3 mutation differences in the human population, then we can estimate how long the average population of human population will be. 3 mutations. Therefore, if we assume that the common ancestors of humans and chimpanzees lived 5,000,000 years ago, the equation would be:

A correction must be made because multiple nucleotide substitutions may occur in any position on the gene over large periods of time. With increasing time, the chances are that the same bases will undergo more mutations than once. Five million years is a long time, so this problem should be accounted for in the equation. There are dozens of ways to correct such errors. In addition, each assumes different molecular evolutionary change patterns. Without entering the details of the process, I will give you adjusted figures to give an example. (Note: These numbers do not represent the actual data, just an example to give an idea of how the numbers are calculated.)

Given the corrected numbers above, we can see that the mutation numbers change (3 -> 3.02 and 65 -> 72.22). The larger number has changed more than the smaller number. This change reflects the fact that mutations are more common, more likely to be more than one mutation in the same subfield. This means there will be some hidden mutations, because the same can be changed a second time.

 

Using such a method, mutations are thought to occur every 6,000 to 12,000 years in the human mitochondrial genome (a mutation every 300 to 600 generations).


 

Acknowledgements

Mitochondrial Clock Update:

Is the idea of ​​maternal mitochondrial inheritance correct ?

Initially, I have been interested in this issue since the re-estimated 6,000 years that mitochondrial Eve lived in the past using the faster rate of mutation discovered for mitochondrial DNA. However, since then, the faster rate has been rejected for all sorts of reasons. Because these abnormal patterns of mutation are contrary to phylogenetic assumptions of evolution, mutations of D cycle are rejected as sorting errors or mutation points. The fact is that no one knows the mechanism behind the mutation rate heterogeneity of mitochondrial DNA. Up to now, in an evolutionary view, there is no good satisfactory explanation for the heterogeneity of the apparent rate of mutation.

In addition to the problem of mutation rate, many of them were contrary to the concept of “African Eve” or “mitochondrial Eve”. Thus, many people began to look for possible causes for increased mutation rate. The only mechanism seen to hold the greatest promise is recombination. Is there any mitochondrial DNA from the father to reconnect the egg with the maternal mitochondrial DNA?

 

First, when the sperm came to the egg, it was thought that it was taken only into the egg of the head, which had DNA (this is a situation where I was taught about people when embryology was done in college). However, during further research; almost all the sperm was laid. Now, the actual images showing the middle part of the sperm in the egg have been drawn. It is now known that sperm DNA is specifically impaired by the enzymes of the ubiquitin system, along with most of the sperm residues. So when the door is open for possible recombination, apparently, it would not normally.

Several patient cases have now been found to have mitochondrial DNA reassembled from both their mother and their father! Many say that the mitochondrial genetics are now more complex than we thought first. Sometimes recombination occurs.

 

Other researchers have returned to the possibility of recombination for long periods with any real effect on mitochondrial genetics. A group emerged saying that the presence of patients with maternal and paternal mitochondrial DNA could only be explained by human error, contamination, and a mixture of samples.

Most or most of these people who recombine mitochondrial DNA are not so sick that they will never have their offspring. Apparently, this unfortunate illness must be a serious thing that makes major changes in DNA, and recombination will never enter the human population.

Just as in the scientific community, when the real populations are examined, I believe that the mother’s inheritance will continue to be the rule. This view is supported by the judicial community, which continues to see the mother’s inheritance in their case, and the Medical community, which continues to use the mother’s inheritance as a source of hereditary advice to the family.

 


Mitochondrial Eve and Clock Vrs. Homo erectus:

Is there a Creation model that will allow the data to fit together?

On the mitochondrial update page, mitochondrial DNA is thought to follow the laws of the maternal heritage. In addition, both the medical community and the judicial community continue to adopt the concept of maternal inheritance in their own case. So we can assume that an early man looks at the Genetic Data and that the mitochondrial DNA follows the maternal inheritance and that the Y chromosome follows his father’s inheritance as assumed before.

 


Since when did the mitochondrial Eve live?

Evolutionists have assumed that the mitochondrial clock speed is quite constant. They assume that mutations occur every 6,000 to 12,000 years (this would be a mutation every 300 to 600 generations). However, assumptions about the rate of DNA exchange are based on the comparison of different species, the existence of common ancestors and the long-term dependence of the evolutionary process involved.

For this reason, the earliest primates such as lemur were thought to have lived 60 million years ago; Wilson and Sarich, in the 1960s, used this thought as a calibration point to measure how a person moved away from chimpanzees. In a highly heated debate, the branch of the human and chimpanzee was beaten about 5 million years ago.

 

Later, in the same laboratory, Cann, Stoneking and Wilson later used a 5 million-year history to calibrate the length of time that the original mother of today’s human population lived. Initially it was thought to have lived 200,000 years ago. The date was set about 150,000 years ago. His pawns are looking for mitochondrial Eve.

If human beings and chimpanzees were not a common ancestor, then these evolutionary comparisons have no meaning.

As a creative scientist, I did not expect the current mitochondrial clock speed to match the rate predicted by evolutionary studies of different taxonomic groups such as chimpanzees and humans. It is an assumption that the comparison of different species shows how long different species have differentiated. If evolution had never happened, chimpanzees and humans had never had a common horse, then a comparative study of different species was not a measure of the evolutionary process; However,

they will be a measure of how similar they are in both tactile physiology and molecular biology.

When scientists began measuring mitochondrial DNA exchange rates over time in a single population, it was shocking that evolutionists discovered that mutations occurred much faster in some populations than expected.

I believe that this faster rate of change is a better predictor of the time when the human is compared to other species and how much DNA has changed significantly. Only evolutionary assumptions occur when the faster rate is held as suspicious. When a different set of assumptions is taken, the faster human mitochondrial genetic rate becomes a distinct possibility to be considered.

Initially, one of the reasons for thinking that mitochondrial DNA may have a constant clock rate is that it will not be affected by Natural Selecia. But as the true non-coding regions of mitochondrial DNA can be extremely rapidly changing regions, the push toward non-natural selection DNA seems to have been abandoned. Now, as evolutionists pair with their own evolutionary expectations, it is the slower rate of change in the coding regions of the mitochondrial DNA that evolutionists now prefer. Nevertheless, they use numbers as if they are unaffected by natural results.

 


Evolutionary belief

Many people do not believe that it is not profitable to entertain even the idea that short ages are possible; Because, in all areas of science, Evolution believes that there is a wide variety of supporting data that serve to consolidate the position of a settled fact or at least the only valid choice.

So, they try to say something like this: “The weight of evidence proves evolution”; or “all the data supports evolution”. But this is not true, the weight of the evidence does not prove anything. We have no problem with the weight of the evidence. On the contrary, what you have is the weight of interpretation!

The weight of interpretations on which the theory of evolution is based. It does not just rely on money.

When you ask someone why they take the position they are taking, or when you start fixing something about a particular supportive benefit, this idea or this idea database is what it is; it starts to break down. “Data supports evolution as a built-in reality,” or it is not true that “data supports evolution, not creativity.”

This discussion is not on the data. The data can go either way. Very intelligent people believe in the long history of the earth and have good givers to support them. There’s no question about that. However, I look at the same data and arrive at very different results. This process is crazy! The database has something like multiple interpretation. There is no evidence for both positions.

All science is dependent on assumptions or hypotheses to simplify the problem, especially in areas of historical interest. Without these assumptions, Science would come to a full stop. Assumptions made by scientists can not be tested, assuming that the natural condition is correct.

So, today they remain as hypotheses, we do not have the ability to test them.

Evolution is no longer a valid theory when one or more of the main assumptions supporting evolution are found to be erroneous. Of course, this would apply to any paradigm used to describe the data, such as Creation or Evolution. Both are dependent on assumptions for their validity.

What is really surprising to me is that while listening to the mainstream sources supporting Evolution I see that they never accept their assumptions.

 


From a creation point of view there is no lock between the two data sets.

An Evolutionary Problem

From an evolutionary point of view, non-African theory collides at the same time against the constant genetic change of the human in different parts of the world, because a set of data rejects the other set of data.

 

Mitochondrial Eve is now thought to have lived 150,000 years ago and 100,000 years ago; it is thought that their grandchildren are beginning to emigrate from Africa. When this happens, they say that old men have disappeared from the earth without leaving a trace in our genetic records! Eve’s invasive line did not hybridize with old man types.

 

Most paleoanthropologists know that this non-African theory is a major problem. They know that the continuity of genetic traits from homo erectus fossils to more modern human forms. There is a direct genetic linkage that can be seen by comparing the various properties of the fossils.

 

Today, the Chinese and other Asians are similar to the old erectus populations, with the straight faces of oriental people. Thus, while mitochondrial DNA data suggests that Asian erectus is consumed in modern oriental humans without any genetic linkage, Two comparative studies say the opposite! The characteristics of modern oriental people are really similar to the erectus populations of the old erectus. So the fossils say it’s really a genetic link!

 

The same phenomenon also occurs in other regions, such as Europe, where modern Europeans are closer to the classical Neanderthal than any living human population with a nose that is really closer to the shape of the back end of the head.

 

When we examine the first problems with mitochondrial DNA studies, it is not surprising that Paleoanthropologists think Milford Wolpoff is “over for Eve”. The genetic study agreed with the fossils in the area.

 

But the Mitochondrial Eve Hypothesis refused to die. Further work by Harvard U. Maryellen Ruvolo helped confirm the Eve Hypothesis by using more modern techniques such as ordering DNA, rather than simply using constraint analysis as part of the work. And Eve’s history was recalculated around 150,000 years ago, 200,000 years ago.

 

1-The mitochondrial Eve data supporting the “out of Africa” theory, the place where the descendants of Eve came from Africa, are seen as

 

possessing the whole world and coming to the top of other human species for 100,000 years without any indication of farming. before.

 

2-The continuous genetic exchange of fossil data in many parts of the world suggests that mankind has progressed in a parallel, multi-regional evolutionary process around the world. If the descendants of Eve have entrusted all the worlds to the whole world, there will be a break in the fossil species seen in the field. The old fossils are not about the new fossil from Havva. By using mitochondrial Eve data, there is no way to explain the continuous change of fossil remains seen around the world.

 


Yazar : Osman TOKER


 

 

 

 

 

REFERENCES


 

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State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, 220 Handan Road, Shanghai, China.

DNA haplotyping Genomics. 1990 Jul;7(3):325-30.CRC Chromosome Molecular Biology Group, Department of Biochemistry, University of Oxford, United Kingdom.

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Mitochondrial DNA sequence heteroplasmy in the Grand Duke of Russia Georgij Romanov establishes the authenticity of the remains of Tsar Nicholas II. Ivanov PL, Wadhams MJ, Roby RK, Holland MM, Weedn VW, Parsons TJEngelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow.

Am J Hum Genet 1996 Sep;59(3):501-9Department of Radiation Therapy, University of Texas Medical Branch, Galveston 77555-0656, USA. nhowell@mspo3.med.utmb.ed

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