The Greater Effects of Bullying, a Look at Monkey Genetics

We have all heard the downsides about bullying, but were you aware that bullying can affect a genetic sequence so as to make you more susceptible to disease and immunodeficiency? A recent study on rhesus macaque monkeys proves that there is some correlation between being bullied and poor health. 

Jenny Tung, an associate professor at Duke University who helped lead the study, set out to find what if any health implications could be associated with social standing.  But first, she needed a subject: enter 49 female rhesus monkeys.  For the study to begin, the monkeys were split into 10 different groups, each with 5 monkeys a piece.  An animal’s social ranking was decided by how early on (or late) each monkey was introduced into the sample group—the earlier an animal was introduced, the higher social ranking that animal was granted by the group.

By examining how the newly introduced animals were treated by their group mates, researchers were able to glean a good deal about where each individual monkey stood socially.  “Lower-ranking females are exposed to a different social environment,” Tung explained of the method. “Day to day, they are subject to more stressful interactions.  There are particular threatening faces and gestures that female macaques can make to each other.  [The low-ranking females] tend to be the target of those threat gestures more often.”

In short, the monkeys with the least amount of time spent in the social setting—those on the lowest ‘totem’ as far as social ranking is concerned—were more likely to also become bullied by the animals that were able to socialize for a longer period of time.  And that was just the start of it, for the next step of the study researchers had to gather and examine the animal’s genes in order to help get a better look at deficiencies that may or may not exist within the fine coding.  While looking at the macaque’s genes, researchers found that those of the lowest order (those treated the harshest by the others) were more likely to have inflamed and, therefore, ‘active’ genes.

Since inflamed genes were directly connected to the immune system, it was then determined that those animals with the higher level of inflamed genes (those under stress, again) were more likely to have a compromised immune system.  Tung found that “When some macaques’ status changed after a newcomer arrived, so did their patterns of immune system gene activity.”

For an immune system that has been compromised, bullying can mean a lot more than harsh words and hurt feelings.  When a person’s health is at stake, bullying becomes that much greater of an issue and not something to be taken lightly.  But just as the topic raises concerns, a possible reconciliation is illuminated.  That is the idea that a sequence of genes can repair itself (or heal, so to speak) as it climbs up the social ladder.  Things like confidence and camaraderie can heal on this very basic level.  “We were able to find that with changes in social environment, you see the gene-expression pattern seems to change with it,” said Tung.  “If you can improve your social environment, then that gene signature seems to go away too.”  And that is something to be confident in.

 

Photo Credit: commons.wikimedia.org/wiki/File:Rhesus_Macaques_-_cropped.jpg

The Keeper of the Male Code, Beaten But Not Destroyed

The Y chromosome, the “keeper of all things male,” has over time shrunk smaller and smaller, leaving many to wonder if the evolution of the male chromosome will lead to its eventual demise. Of course, the change in the size of the chromosome has occurred over millions of years, so any real sign of change would not be expected for quite some time.  But nonetheless, it has prompted many researchers to imagine a future when male attributes would have to find another way to hitch a ride into future generations: perhaps even leading to a new dawn of immaculate conception.

A group of scientists led by David C. Page and Jennifer F. Hughes, at the Whitehead Institute of Cambridge, Massachusetts, have worked hard to piece together the long history of the Y chromosome in order to get a better idea of where it would be going in the future.  What they found was that despite a history of dramatic change, the Y chromosome has all-in-all hit a lull that has lasted some 25 million years.  According to Page and his colleagues, the Y chromosome has gone through a series of stages that began approximately 320 million years ago, when the chromosome first appeared and culminated in the decreased size of the chromosome through the millennia.

In its earliest stages, both the Y and the X chromosome were the same size and held the same number of genes.  Now, the sides are severely skewed with the Y chromosome containing no more (and possibly less) than 30 genes to the X’s estimated 800.  This has happened because of the Y’s “self-sacrificing” of its own genes in order to lend a hand and safeguard the feminine X.  In doing so, a sort of no-swap area was determined on the Y chromosome in order to protect the Y chromosome from complete eradication. And over the millions of year since its first appearance, this no-swap area has gradually grown to encompass practically all but the very tips of the chromosome.

It is because of this self-effacement that the Y chromosome now contains much fewer genes than it once had. However, that is not to say that the Y chromosome is not important. In fact, it is because the chromosome contains such important attributes, namely, the male genes and the gene that determines sex that the Y chromosome will never completely disappear— at least not any time soon.  “We can confidently say that the decay of the Y chromosome has come to a halt, and that would portend very well for its future,” explains Hughes.  “If you draw a straight line, the Y chromosome’s demise would come four or five million years from now,” adds Darren Griffin, a professor of genetics at the University of Kent in Canterbury.

Researchers gained this insight by breaking down the genetic code of the rhesus monkey, an animal that shares a common ancestor with humans from the same time that the Y chromosome last gave up many of its genes. Because of this new information, believers of the “rotting Y” theory can rest assured that the Y chromosome will be here for a while.  “It’s my sincere hope that this article might put the notion of the disappearing Y chromosome to rest,” adds Page confidently.

And for now anyway, it seems that it has.

 

Photo Credit: nist.gov/mml/biochemical/images/y_chromosome.jpg