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One of the most vital substances to an organism is its genome in its DNA, which is often prone to mutations which can be harmless or have a devastating effect on the organism. An article detailing some of the findings made by a group of researchers at Penn State entitled “Unusual DNA folding increases the rates of mutations” explores the effects of the shape of strands of DNA on organisms in terms of evolution, mutations, and advancements in the medical community. A normal strand of DNA is configured in the shape of a double helix, which is referred to as “B-DNA”. When a portion of DNA is in a shape other than the double helix, or “non-B-DNA”, the team found that it has a much higher rate of genetic mutations occurring during DNA synthesis. In order to prove their hypothesis, the research team compared the genomes of many different humans, where they looked for mutations of singular nucleotides in the genetic sequences. Using statistical analysis techniques, similar to the chi-squared equation, the team of researchers was able to determine that the significantly higher rate of mutation in non-B-DNA strands was caused by something more than chance, likely the shape in which the DNA was configured. Because these strands have such a high rate of mutation, they are significant contributors to genetic variation. Should these mutations be helpful for the organism, they are more likely to be passed onto offspring through reproduction. This phenomenon is essential for aiding the process of evolution. The finding made by Penn State will be useful in the medical field as well, as humans with significant amounts of non-B-DNA are more likely to develop genetic disorders caused by the mutations more often produced in non-B-DNA strands.
This discovery connects to our class, specifically chapter 16, in which the shape of DNA is being explained. The double helix structure is important for accurate DNA replication, and without it, it is much more difficult to adapt the DNA replication system to work with an unusually shaped strand, leading to a higher chance of genetic mutation. Unit 5 explored the way in which genetic variation occurred (such as mutations, crossing over, and the use of two sets of DNA in sexual reproduction), and the mutations of non-B-DNA lead to a high amount of mutations. This unit also increased knowledge of statistical analysis, specifically through the chi-squared technique. Accurate statistical analysis was vital to the findings of the study, as it showed the high rate of mutation in non-B-DNA strands was due to something more than chance. In addition to connecting to the course, the research done at Penn State is important to improving prediction and analysis of genetic conditions. It is also helpful in better understanding evolution and the effects that genetic variation (such as mutations) have on the genotype of a region of organisms. Scientists are always discovering new knowledge about biological systems, which is essential for the improvement of the quality of human life in fields such as medicine.