BIO 1165

MtDNA is very important to this article. What is MtDNA you ask? It is the
Mitochondrial DNA which are the genomes in the mitochondria. The genomes in the mitochondria are much smaller than the genomes in the nucleus of a cell. (Taylor and
Turnbull) It is important to understand this basic concept, because in the study they are looking at the mutations of the MtDNA and how they affect human disease. The scientists in this study are doing this research to try and determine what these mutations will do to human’s health. This would be a good thing to know, unfortunately they need more research to determine the reasons it affects human health and how it affects the health and why it affects the health of humans. The only thing this study really lets us know is that we know that it does affect human health. In this article a hypothesis is not stated directly but I believe the hypothesis is mitochondrial DNA mutations cause human disease. This is pretty much explained in the title of the article. (Taylor and Turnbull)
To study the mutations they needed animals with heteroplasmic and pathogenic mtdna mutations. This can prove to be difficult to find and in-vitro was not an option either. To experiment they would obviously need an animal, (living animal), to observe the affects of a mutation in the mitochondrial DNA. (Taylor and Turnbull)
They did create mice that had these traits by fusing different types of mitochondrial genes in the zygotes together. By doing this they created the type of mutation they were wanting to study. (Taylor and Turnbull)Fortunately we can’t just use people to test and study on in the first phases when we’re not 100% sure of what’s going to happen in experimentation.

In this experiment, they looked for any signs of abnormal health, since that was their hypothesis. When they found abnormal signs of health their hypothesis was confirmed. If they did not have a hypothesis their experiment would have been for nothing, because you can’t form a procedure without a hypothesis or an observation to base it off of.
The results showed that the mice with these mitochondrial DNA mutations developed diseases such as muscular defects, cardiac defects, and mostly renal failure.
This according to the article means that the DNA mutations in the mitochondria cause species specific symptoms. (Taylor and Turnbull)
Since it was only a hypothesis before the experiment started we now know that the hypothesis may be correct, the evidence of mice does not necessarily prove that humans are the same way. The evidence is very compelling to assume that it is the case though. However until more studies are done and the studies go into human trials then we can’t know for sure that it is the case. (Taylor and Turnbull)
The results are important because now that they know that mitochondrial DNA mutations affect mice this way, they can proceed to further experiments involving more specific questions. They could figure out the different types of mutations and isolate the specific mutations to figure out which causes what disease. Once they figure out after all the studies they performed isolating specific mutations they can figure out how to treat the diseases caused by these mutations. Without further exploring this general study they won’t be able to do this. Without the general study being done; however, they would not be able to even begin to figure out where to start. (Taylor and Turnbull)

Taylor, Robert W. and Doug M. Turnbull. Mitochondrial DNA Mutations in Human
Disease. May 2005. July 2014
<http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1762815/>.