How Clever are Octopuses?

In recent studies, researchers have discovered that octopuses are able to change the message sent from their DNA, instead of following it like most organisms. Scientist have suggested that because octopuses can alter their genetics, that its a reasonable thought for why they are so intelligent. Octopus are capable of solving complex puzzles and changing colors to communicate. The genetic change occurs in the protein synthesis- where RNA is coded into amino acids, and that is where octopuses do not follow the genetic instruction. RNA editing is known to affect the nervous system, which might be a necessity of these organisms lives in order to live.

I think the discovery of RNA editing in cephalopods changes the idea of importance of RNA editing. With this discovery, I think this gain a better understanding of genetic sequences, but also broadens the concept to learn more about these intelligent organisms and others.


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European Diseases may have Genetically Changed the Immune System

Around the 15th century, European settlers migrated towards America, coming in contact with Native Americans. Not only did they bring new perspectives on religion, but they brought diseases that ultimately killed a large number of Native Americans. Researchers have begun a study on how diseases stemming from the 15th century have affected the modern immune system genetically.

The immune system is designed to protect your body against bacteria, toxins, viruses, etc. As your body becomes infected, the antibodies, proteins that attack viruses, fight it off for the first time. If the same infection enters your body again, then these antibodies are able to recognize it much faster, and respond accordingly.The Europeans were typically more exposed to smallpox, measles, and influenza. Different antibodies were developed due to the diversity of disease and the different groups of people affected with these diseases.

A research team has decided to analyze the DNA from the remains of 25 people that lived in the general area 500-6000 years ago. Most of these remains were from those who encountered Europeans in the 1700s. They used a process called whole exome sequencing. They searched for genes related to the immune system. They also sequenced 25 current Tsimshian residents. After comparing both sequences, researchers noticed that some variants of the genes related to the immune system were rare among those that were living. HLA-DQA1 is one of those genes that was found in all ancient people but only found 36% of the time in the living ones.

Researchers believe that these genes were adapted to the local diseases but not to the new ones. They predict that the genetic shift occurred about 175 years ago. After this finding, researchers would also like to do a study on the immune related genes in other Native American communities.

This study is very interesting because it explains how the immune system has changed over time. It didn't just evolve as a way of being able to fight off infections much easier. It evolved with the genetic aspect as well, leading to much more research that could possibly be done.

http://www.sciencemag.org/news/2016/11/european-diseases-left-genetic-mark-native-americans

https://www.broadinstitute.org/blog/what-exome-sequencing

Evolution in Action

In hatcheries, fish live in more crowded conditions and eat different food than wild fish do.  Genetic change in hatchery populations would be no surprise.  What was a surprise was the sheer amount of change found after only one generation of hatchery fish in a study conducted by the Oregon State University and the Oregon Department of Fisheries and Wildlife.  They found that first generation hatchery steelhead trout and wild steelhead trout had differences in the activity of over seven hundred genes.  Many of these genes were involved in wound healing, immunity, and metabolism.  According to Mark Christie, the study's lead author, these changes are consistent with what is expected in the early stages of domestication, when animals adapt to more crowded conditions.  The researchers hope that by better understanding the genetic changes caused by the hatchery environment, the methods of raising fish can be changed so as to maintain a closer degree of similarity to the wild fish.

It makes sense that the genetic changes associated with living in captivity would involve metabolism, because of the change in diet, as well as wound healing and immunity, because with more crowded conditions the incidence of injury and disease increases.  The number of genes involved in so short a period of time is surprising, but more understandable when you consider that a sudden change in environment will probably kill off individuals unsuited to the new environment more quickly than will a slow change.  That's not accounting for any epigenetic changes or artifical selection of the healthiest fish that may be going on at the same time.
As far as raising captive fish to be more like wild fish is concerned, it follows that if they are raised in conditions more similar to those that wild fish live in, they will be more like wild fish.  What genetics has to do with it, I don't know.