The Evolution Of Mitochondrial DNA

Some researchers believe the Out Of Africa expansion took a southern route, following the Indian Ocean coastal boundary down in to Indonesia and finally into Sahul (Bar-Yosef and Belfer-Cohen, 2013; Derricourt, 2005; Field and Lahr, 2005). However, genetic testing of aboriginal inhabitants of Sahul favors a combination of southern and northern routes. The northerly migration path traversed through the Altai Mountains, and shows a consistency with Denisovan genetics (Cooper and Stringer, 2013:321; Davidson, 2013:3). Modern human gene flow with Denisovans is believed to have occurred in the mainland area of Asia, before migration to Sahul (Cooper and Stringer, 2013:322; Reich et al.,

“All four Neanderthals yielded the mtDNA sequences similar to those previously determined from Neanderthal individuals, whereas none of the five early modern humans contained such mtDNA sequences. In combination with current mtDNA data, this excludes any large genetic contribution by Neanderthals to early modern humans, but does not rule out the possibility of a smaller contribution” (Serre, 16 March 2004).

- Dna tests on the mitochondria genome are used to expose a common ancestry or a genealogical connection up to 10,000 years ago to today.

Neanderthals lived from 130,000-30,000 years ago and were part of the Archaic Homo sapiens; meaning the Homo neaderthalensis were an earlier member of the modern humans. The living range for the Neanderthals located from Europe to the Middle East. About 50,000 years ago modern humans started to migrate from Africa to Europe and the Middle East, thus causing Neanderthals and modern humans to interbreed. In the two articles “Researchers shed light on Neanderthals’ legacy in humans” and “Surprise! 20 Percent of Neanderthal Genome Lives On in Modern Humans, Scientists Find” they discuss how some genes and phenotypes found in Neanderthals were also expressed in non-African descent modern humans and reason behind it. The study between the Neanderthals

Although modern humans are of the only surviving ancestors in today's society other groups of early humans did used to walk where we walk. Which is why the greatest mystery and biggest question of human evolution is what happened to the Neanderthals. Neanderthals were the early group of humans who used to live in Europe and Asia thousands of years before Homo-Sapiens took over the world population. Many believe Neanderthals died off leaving nothing behind but scientist have provided that most humans have neanderthal DNA within them. Leading people to believe that our ancestors had interbred with Neanderthals. As Neanderthal DNA is 99.7 percent identical to modern human DNA providing that Neanderthal genes continue to lurk on within modern

Lawrence Livermore National Laboratories in Livermore, California has found that human hair could replace it in which DNA evidence is either damaged or nowhere to be found. Similar to DNA, the test on a patient’s hair can not only could identify an individual but trace his or her ancestry. This new test is a reliable alternative to DNA identification, since DNA is very fragile and will start to decay over time. Hair does not actually contain nuclear DNA which is the chemical which is inherited from both parents. However, it contains mitochondrial DNA which is passed down matrilineally.

We often have misconceptions whether we share some DNA with common ancestors and we now have the ability to fully understand that we do. When people first meet, they often ask where we are from and respond with an ethnic background, but do not take the time to realize how we came to be. Not many think back to the time where modern humans truly became modern humans and see if we even shared DNA with them. Not many like to admit that they share DNA with those who were “clueless and lived in caves”. One of our common ancestor, Homo neanderthalensis, were found around 400,000 to 40,000 years ago in most of Europe and Southwest Asia (Smithsonian National Museum of Natural History, 2016). Upon discovery, scientists were able to use the combination

However, the ME for the mitochondrial 16s rRNA shows that gorilla is more closely related to the chimpanzee and the bonobo, when compared to the other primates (Figure 11.3A). Furthermore, all of the four trees produced show that modern humans and Neanderthals appear as a monophyletic clade 100% of bootstrap replication times which supports the first hypothesis stating that Neanderthals would be the closest relatives to modern humans, when compared to the other primates (Figure 11.3A, 11.3B).

While there were many genetic differences found between Neanderthal and modern human DNA, there was also a number of genetic overlap. Genomes were taken and sequenced from Africans, New Guinean, Han Chinese, and French (Green et al. 2010). Genetic overlap and similarity was found among the French, New Guinean, and Han Chinese but there was no significant similarity found between the African genomes (Green et al. 2010). In addition, data was taken based on haplotypic differences. If there was considerable gene flow from Neanderthals to modern humans, it would be suspected that there would be similarities between Neanderthals and non-African haplotypes when compared to African haplotypes. The data found that there were haplotypes found among

The author of this book, Brian Sykes, presents his discoveries regarding the possibility that all humans branched from seven main clans. The book focuses mostly on the ancestors of Europe and the East. He supports his findings with the evidence of mitochondrial DNA. Sykes explains that mitochondrial DNA can be traced back to the original matriarchal ancestors. His findings showed that people from certain parts of the world had mitochondrial DNA that related more closely to one of the seven clans. Each of the clans has some defining characteristics which make it an more reliable source of lineage rather than ordinary DNA, which has become muddled throughout the generations. He presents the women of each clan with enigmatic names: Helena, Xenia, Ursula, Velda, Jasmine, Tara, and Katrine. He also explains the advances in genetic science, which he uses to explain the studies presented. The studies regarded Polynesian islanders, the Romanovs, the hunter-gatherers in Europe, and many others.

As an expert on human genetics, Sykes details the specifics of mitochondrial DNA and how it relates to human evolution. Mitochondrial DNA is a type of genetic material we inherit only from our mothers, which he uses to establish maternal family trees for the history of the human race. He accomplishes this mission through the examination of tiny variations in different individuals' mitochondrial DNA and proceeding to

DNA phenotyping serves to determine the physical attributes of a specific individual based off of genetic material that was left behind at a crime scene. By being able to determine physical traits such as hair color, eye color, height and skin pigmentation researchers can narrow in on the appearance of a person who committed a crime. This is crucial in forensic genetics who’s geneticists play a vital role in investigating crimes and in turn play a

Ancient DNA has been used to show aspects of Neanderthal appearance. A fragment of the gene for the melanocortin 1 receptor was sequenced using DNA from two Neanderthal specimens from Spain and Italy: El Sidrón 1252 and Monte Lessini. Neanderthals had a mutation in this receptor gene which changed an amino acid, making the resulting protein less efficient and likely creating a phenotype of red hair and pale skin. Modern humans display similar mutations of MCR1, and people who have two copies of this mutation have red hair and pale skin. However, no modern human has the exact mutation that Neanderthals had, which means that both Neanderthals and humans evolved this phenotype independent of each other.

During the 1980s, three specialists, Allan Wilson, Rebecca Cann and Mark Stoneking, worked together on another theory that supports Charles Darwin's speculation, the “Mitochondrial Eve” hypothesis. In these tests, the scientists solemnly focused on mitochondrial DNA, human genes that lay within the cell and are passed from mother to child. These genes allow mutation, as they mutate quickly for adaptation, thus allowing those studying to find and track changes during short time periods. By focusing on these genes and comparing their differences, the three scientists were able to create a hypothesis about the time and place when modern humans began to evolve. According to their findings, they believe that modern humans are decentants from a single population, while earlier humans e.g. Neandertals and Homo erectus, had become extinct. Furthermore, the team compared the DNA of numerous people of differerent ethnic backgrounds and concluded that all humans did indeed evolve from 'one mother' in Africa about 150,000 years ago.

DNA is deoxyribonucleic acid, which is found in almost all living things. DNA serves as a code for the creation and maintenance of new cells within an organism. Within humans, it is found in almost every cell. Although most of our DNA is found within the nucleus of our cells as nuclear DNA, a very small amount of our DNA is also found within the mitochondria as mitochondrial DNA. Because mitochondrial DNA is generally not used for solving crimes, for the purpose of this paper it will be disregarded.