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Y-Chromosomal Adam is much the same as Mitochondrial Eve, yet with a paternal twist. With, Adam, the y-chromosome is used as a possible defining point in finding a paternal ancestor.
How Does He Carry the Paternal Link?
The search for a paternal companion to the mitochondrial Eve has clearly been focused on the SRY gene on the Y-chromosome. However, it should be noted that Y-chromosomal Adam is not at all from the same time period as Mitochondrial Eve. By tracing back mutation rates, it has been found that the rate of mutation for the SRY gene on the Y-chromosome is derived from a man who lived 60,000 years ago. This is extremely different from the predicted 170,000 year origin of the maternal mitochondria or Mitochondrial Eve. Geneticist, Bryan Sykes studied this radical difference between the two origins and found that the maternal mitochondria had undergone a smaller amount of mutations in comparison to the Y-chromosome. Therefore, it is easier to trace back and compare mutation rates in mitochondrial DNA than it is in the y-chromosome. This means, the maternal lineage has perpetuated much longer than the SRY gene.
Basically, this means that by some chance, the y-chromosomal DNA of some man 60,000 years ago, was dominant and was able to continue on from his children onto the following generations until it spread throughout the populace and diminished other y-chromosome contenders. However, this also means that at some point, Eve’s and Adam’s DNA amalgamated and coincided into one single set of DNA which spread to the many genetic clusters around the world.
However, the discovery of Y-chromosomal Adam has been a fairly new theory and it does have some setbacks. Firstly, the Y-chromosome has displayed a decrease in the number of chromosomes from each generation. This means, that the Y-chromosome is diminishing more rapidly as time passes. Therefore, it becomes hard to analyze a set of DNA that is getting smaller generation after generation without us knowing why. This is why mDNA can be traced back further than the Y-chromosome. Although the Y-chromosome aids in finding paternal lineage, it still has been found to be less reliable than its maternal companion.
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