Tuesday, March 13, 2018

Climate Change and Dna Mutation Rate

Some people have wondered how I came to my dating and conclusions about the age of dna haplogroups. I have mentioned that I do not believe there is a constant rate of mutations over recorded history. The problem with many algorithms used to date haplogroups is they take either an evolutionary molecular clock method or one based on the present germ-line rate of mutations. Neither methodolgies are correct but the germ-line approach is closer to the truth than the evolutionary molecular clock approach.

I have mentioned in my writings that drastic climate change whether caused naturally or artificially increases the rate of mutations as well as the effects of radiation. I have stated that during the Medieval Warm Period and the Little Ice Age the mutation rate became more rapid. It would seem that my conclusions were confirmed by a scientific study published in 2015 that climate change increased the mutation rate in a study by John H. Wilson with the Department of Molecular and Human Genetics at Baylor College of Medicine in Houston in Texas.  Paul Hamaker reported that: 

 "...Wilson and colleagues found that extremes of heat, extremes of cold, oxygen deprivation, and oxidative stress all produce higher rates of mutation in the regions of human DNA that are most prone to mutation. Climate stresses have a unique pathway to produce mutations that involve the stimulation of DNA rereplication. The researchers found that limiting the availability of replication origin-licensing factor CDT1 reduced the rate of mutation...."

They also concluded that these changes in the rate of mutations may affect the process of natural selection in both positive and negative ways. However  I think that as mutations always involve some loss of information this in the long run may limit the adaptability of those groups who had those mutations.

I have also proposed that in the past before 400 BC there would seem to be group mutations caused by cataclysmic events in the world's past. Instead of just one person mutating, the events caused all those of the same haplogroup living in the same environment to mutate in the same manner. Thus instead of assuming that a certain single chief passed on the mutation, the chief and his whole tribe mutated in the same manner and passed on the mutation. Of course those who share the same mutation would eventually be able to trace back to a common ancestor even though that ancestor may not have had that mutation and nor did his descendants for many generations before it occurred across his numerous descendants in one locale who passed it to their descendants while his descendants in a different locale may not have mutated or may have mutated differently.

I have also previously stated that y-dna can be influenced by the mother and her inherited dna in some cases. It is also possible that mt-dna may be influenced by the father's inherited dna. Thus it is possible that a child may inherit a mt-dna mutation from their father's mother or a y-dna mutation from their mother's father.

I also have mentioned how dna is often not available or so degraded that it is unable to be tested in bones before about 1960 BC due to the hot humid weather experienced after the Flood. Thus it will be difficult to ever understand the periods before 1960 BC through the testing of pre-1960 BC ancient dna. However we can exam the earlier in history of dna by the testing of bones after this period and by living dna. The erroneous evolutionary dating of ancient artifacts and the erroneous chronologies of ancient history especially of Egypt makes this process more difficult.

Other scientific studies have demonstrated that even a mildly stressful environment will increase the mutation rate as do levels of fitness. It has also been demonstrated that the mutation rate is also more rapid in in-breeding populations than out-breeding populations. Thus there are many diverse factors to take into account when using and interpreting the actual dna evidence. Of course one's world view can also affect one's interpretation. Those who have blind faith in evolutionary theories try to fit the evidence to their assumptions as do those who accept a so-called Creationist world view. Another factor to take into account is the possibility that man himself has caused certain mutations through genetic engineering in the past when civilisation may have been even more advanced than today.

My own approach includes evidence from dna results and studies, genealogical and archeological and historical evidence which for me seems to confirm a much younger age for man. However in the area of science I try to be open to the understandings and theories of others as well as open to the possibility (God forbid!) that I may be mistaken or wrong. I probably wasn't very diplomatic but certainly sanguine when I told my high School biology teacher; "Miss, looking at you I can see that your ancestors may have been apes but mine were obviously Divine Creations"!!!

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