First validated canine behavioral genetics findings of nine fear, aggression traits in dogs

Although anxiety has been a topic that is well-understood regarding what exactly happens to the body, little is known about the genetic variation causing anxiety; so a study was conducted focusing on the genetic cause for aggression in dogs, which can frequently be read through their body language since we communicate in different ways. But, although there are several breeds that have unfair, negative stigmas, there are a few breeds that have been proven to be more fearful or aggressive when compared to other breeds.

Scientists found 12 genes linked to traits in which the predisposition of aggression towards a familiar person or animal is distinct from that of new, unfamiliar people/pets. They discovered the genes in two genome regions which were consistent with the core fear/aggression neural pathway, otherwise known as the amygdala to hypothalamic-pituitary-adrenal-axis.

According to the scientists, the results are relevant to the most serious dog aggression problems, and should likely correlate to human anxiety disorders as well. They hope to eventually determine which neuronal circuits are affected by the risk variations, which could aid in locating drugs that could alter the behavioral effects. If successful, the goal would then be to determine the appropriate drugs for humans and develop a new drug therapy/treatment. Scientists say that if they identify the affected pathways, then biomarkers can be used to see who would positively respond to the treatment.

Anxiety is the most common type of mental disorder in the United States which validates how essential identifying the link between genetics and anxiety would be. Not only would we gain a deeper understanding for man's best friend, but it would benefit the human race immensely in terms of possibly alleviating the strains of a mental illness, or at least educating oneself on what to do if you're genetically prone to anxiety.

https://www.sciencedaily.com/releases/2016/08/160810180908.htm

The Genes Behind Why Dogs are Man's Best Friend

   

 “Dogs are man’s best friend” is a very common quote used to describe the fondness and loyalty dogs have for humans. Surprisingly, research shows that the same genes linked to social disorders in humans, such as autism, are possibly the same genes behind dogs’ social behavior towards humans.

The behavioral experiment in which dogs’ sociability towards humans was tested.

    A behavioral experiment was conducted using hundreds of lab-bred beagles, in which they were given a task to open three transparent lids containing treats, one of them being tightly closed. The dogs were observed to seek help from the person standing in the room after finding it hard to open that lid, instead of finding a way to open it on their own. Some of them looked at the observer and then back at the stuck lid, while others tried to make physical contact or stayed close to the observer. The Gender of the beagles was also shown to play a role, in which females were shown to be more sociable than males.

    A DNA testing method, called Genome-Wide Associated Studies (GWAS), was used to study a large number of variants within each dog’s genome. Results showed that five genes selected during domestication were heavily linked to dogs’ sociability towards humans. Four of these genes, including the SEZ6L gene, have also been linked to human social disorders, such as autism, schizophrenia, aggression, and ADHD. The evidence however, is not enough to prove this correlation, since this test was only performed on beagles. Scientists plan to do further research on other dog breeds, and hope that this information would also be useful in gaining a better understanding of human social disorders.

    I found this information very fascinating because I never knew that a gene that can possibly be beneficial in one species, can be harmful in another. I’m looking forward to reading more about this when further research and confirmation are made.

Links:

https://www.sciencenews.org/article/gene-linked-autism-people-may-influence-dog-sociability

http://www.scienceworldreport.com/articles/48744/20160930/genetics-now-explain-why-dogs-mans-best-friend.htm

http://www.dailymail.co.uk/sciencetech/article-3813873/So-S-man-s-best-friend-Genes-linked-autism-humans-influence-dog-sociability.html

Aggressive male Chimpanzee's will father more offspring

Research has found that male chimpanzee’s that are more aggressive toward females tend to father more offspring over time. Joseph Feldblum and his colleagues from Duke University conducted the research in a chimpanzee community that was living in Tanzania’s Gombe National Park that has been under close observation for the last 50 years. The community was so well watched that, it was know that who mated with who and also who the biological fathers of almost all of the chimpanzees born since 1995 were, because of the genetic tests done.

When examining the aggressive males, they looked at two different periods that the female chimpanzees go through. A period of time when they were sexually receptive and swollen compared to a period when they were not. Following the observation, their analyses showed that the males that were aggressive with the females during the swollen period were more likely to mate, but they did not have a greater paternity success. As for the high-ranking males that were aggressive with the females during the period when they were not swollen, they produced more offspring. Therefore, the results show that long-term patterns of intimidation give high-ranking males a higher number of offspring. This is the first example of genetic evidence of sexual coercion that is used as an adaptive strategy in any social mammal.

I found this article interesting because the title made me curious on how intimidation could help a male produce more offspring. However, after reading the article I understand how common aggressive male-female relationships are in chimpanzee populations. Therefore, it totally makes sense that in order to mate and reproduce with the females, it is necessary to be more intimidating and aggressive in order to be more successful. 

This Article: Intimidating chimpanzee males are more likely to become fathers

Genes Active in the Brain of Rats Show Aggression or Tameness

In the journal, GENETICS, research has been published about the differences between aggressive and tame rats and how it is caused by the genes in their brains. This study can further previous research about what genes make animals tame. It shows us which genes make tame dogs and their wild ancestor, wolves different. According to co-author Henrike Heyne of the Max Planck Institute for Evolutionary Anthropology and the Unviersity of Leipzig in Germany, all domestic animals are tame and this research allows us to understand the reasons why wild animals transform to domestic animals.

Dmitry K. Belyaev, famous for his work on experimental domestication on foxes, and his colleges used 200 descended rats from a study he did over forty years ago. The purpose was to separate the rats into two groups: ones that show aggression and fear and ones that are tame and friendly. The groups were based off of when a human hand approached the rats: aggressive rats attacked and showed fear towards the hand while the others were intrigued in the hand and allowed the hand to pick them up.

The researchers created a population of hybrids by crossing the rats from each group to find gene variants responsible for the differences in behavior among the rats. The hybrid rats showed "a wide range of behaviors and inherited a random mix of genetic variants from the original tame and aggressive parent rats." Eight regions were identified in the genome by the research team which signified genetic variation in the tameness gene. Heyne and colleagues analyzed brain activity to discover that eleven genes in these regions made them "more active in the brains of aggressive rats compared to tame rats, or vise versa." Five of these eleven genes were noted to influence behavior of the rats, which may be the driving force of differences between the two groups of rats. "Several of the genes are involved in nervous system development, and one, Slc17a7, has previously been implicated in fear and stress behavior in mice."

Although further research is needed to determine which genes specifically trigger aggression and tameness in mice, this experiment gives us great insight for the possible outcomes. According to Mark Johnston, Editor-in-Chief of GENETICS, this work done allows us to better understand "genetic details of a biological process that has been pivotal to human history." If we are able to identify which genes cause aggression and which genes cause tameness in mice, there is a great possibility that many wild animals will be tested on and domesticated. If the testing is allowed, humans will most likely figure out a way to control wild animals and breed them in ways that are beneficial to us. On one hand, this concept is mind boggling to think that this may be able to be done with technological advancements. Many people will probably have exotic pets, and try to advance one another to  have the most "unheard" of animal as a pet, which could get out of hand. This advancement can devastate wildlife as we know it and completely change the way we interact with nature: our idea of nature will be man-made at that point.

Article:
http://www.medicalnewstoday.com/releases/285139.php

Related Article:
http://www.genetics.org/content/198/3/1277.long

Angry Mice

When sexual reproduction happens there is a process called imprinting that happens. This process is the act of activating genes from either the father, or mother side of the parentage. Researchers have recently uncovered that lab mice with their fathers gene Grb10, caused the mice to be more aggressive. This social dynamic was found by a group of scientists that were at the Department of Biology & Biochemistry and Centre for Regenerative Medicine, University of Bath, Claverton Down, Bath, UK  and was published in the Nature Journal. This group found that mice altered during embryonic growth to shut off one gene and always activate another showed dramatically higher aggression in social situations. "Thus Grb10 is, so far, a unique imprinted gene, able to influence distinct physiological processes, fetal growth and adult behaviour, owing to actions of the two parental alleles in different tissues." Most importantly, humans carry this gene as well. And what proves true for lab mice may prove true for us as well.