A little bit about myself…I did my undergrad and graduate studies in Germany at the University of Göttingen. After I finished my PhD, I moved to New Haven, CT, to work as a researcher at Yale University. I myself am interested in brain networks that govern behavior. How they assemble, what do they look like and how they change behavior. I chose to work on the fruit fly Drosophila melanogaster, for the reason that they offer easy access to genetic manipulation, reproduce quickly, and most importantly, because the genes between human and flies are are similar. Just as an example, one of the most important genes regulating our sleep/wake cycles (the behavior the researchers in the Yale lab are working on), the gene period, was first discovered in a fly mutant. We and other labs all around the world are now using the genetic tools available for Drosophila to gain a better understanding of how genes shape this kind of behavior.

One of the most versatile tools we have in our arsenal is the GAL4/UAS-system (often referred to as the geneticists swiss army knife). With this system we are capable of expressing genes of interest in a defined subsets of cells (e.g. the nerve cells that are responsible for the daily rhythm of the fly). In this system we have two parts that regulate the expression of genes. One is the GAL4, which is a protein from yeast that activates transcription, but only of proteins found in yeast. What we do is to generate flies that have the gene for GAL4 in their genome. Then, we put a base pair sequence in front of the gene that would normally regulate the expression of a fly gene (this sequence is called a promoter), so that the GAL4 is now only expressed in the same cells that would also express the fly gene. Next, we generate a fly that has a copy of the gene for GFP in its genome. In front of this gene we put a UAS-sequence, this stands for Upstream-Activation-Sequence. The UAS-sequence is important because the GAL4-protein can bind to it and activate transcription of the GFP. If we now cross the two flies with each other the offspring will produce the GFP protein only in the cells in which the GAL4 protein is expressed. On the picture below you can see an illustration of how this technique works and an example that shows a fly brain in which GFP is expressed in very specific brain cells that are responsible for daily rhythms.

Why do you think it is better to have a two parted system for gene expression then just putting the GFP under the control of the promoter?

Over the last two decades laboratories all over the world generated thousands of fly strains that express GAL4 in different tissues and also thousands of flies that have different genes under the control of the UAS-sequence. From this, various genes and networks can be discovered that are important for such behaviors as sleep, learning, and decision making.

Students of different "races" at my school

Today upon asking my parents, who were raised for the majority of their lives in a communist country, if they believed in the concept of race, they responded by saying “of course”. I then proceeded to ask my brother, who was born in the United States and is now 12 years of age, and he too shared the same idea as my parents. I asked him to define race which he described as a difference in skin color.  Then, I gave him a situation where if I, a Caucasian male, were to tan to the point where I appeared brown, was I still considered Caucasian although I resembled a Hispanic? He responded by saying that I still should be considered white.

Race, with multiple non-coherent definitions on the web, always seems to be a topic that people elude and define very vaguely, the majority saying that the definition of race varies across cultures (what we consider as “white” is not considered “white” in Africa for example) and overtime while others state it simply as the color of a person’s skin. This in return brings up the question, Does ‘race’ really exist?

Although race is a form of identity for people and it instills them with a form of pride, the negative effects of race seem to overlap the positive ones. Look at Social Darwinism. This concept was used to promote the thought that the white European race was superior to others, and therefore, destined to rule over them. Racism even in 2010 is not over. I mean it can’t end as long as we are allowed to believe and think what we do about race. Look at this site for example which states that “African-Americans are directly targeted and punished in a much more aggressive way than white people”. Is it surprising for you to learn that the police stop blacks and Latinos at rates that are much higher than whites?—about 80% of the NYPD stops were of blacks and Latinos—From these negative effects I get a feeling that race is just an excuse for people to disagree and fight.

Humans are said to be 99% identical to each other genetically. What this implies is that we are all born with a similar layout–arms, legs, ears, a brain, a heart–yet when it comes to filling out an application for a job or other occasion we are always posed a question to identify our race in order to define our demographics. Yes, it is true that we all come from different backgrounds–African-American, European, Japanese, Indian, Taiwanese, Chinese, Filipino, Mexican and Vietnamese to name a few—but in the end we are all linked to the same ancestor. So now ask yourself “What race am I?” Some of you might say Caucasian others Asian, but why do we have this misunderstanding of Race?

Look at it from a biological/scientific standpoint. The variation in skin color as a scientist might explain it is an adaptation by the human population mainly due to two major factors, physical barriers such as mountains and oceans and secondly climate. These foresaid barriers restrict interbreeding among people who have different genes, think about it, an Asian couple will mate and produce an Asian offspring, a Caucasian male mating with an African-American women however can produce either a Caucasian or African-American offspring. Climate on the other hand influences skin tone through exposure to sunlight. When the sun’s ultraviolet rays come in contact with your body, they begin to break down the DNA in your skin. In response, special cells called melanocytes release a pigment called melanin. The melanin turns your skin darker in an attempt to shield your skin from the sun’s rays and protect it from further harm.

As you can see “race” is just variations among humans (not genetically) and as a result we can’t justify the separation of “races”. Why believe in race when scientifically and biologically, which through facts and evidence such as the ones stated above, prove it doesn’t exist. I would understand if the concept of race improved our society but in my eyes it hasn’t, there is racism occurring in all parts of the world, people are dying as a result of this “difference” we see in people when in reality it’s just a belief rather than the truth.

Imagine a world without race, where people aren’t hypercritical of each other just because of the color of their skin, it almost sounds too good to be true. I believe that we must not be afraid to talk and teach about racism and one way to help change attitudes about race and defeat racism is to educate children about the historical problems that racism has caused, and let them know that the only way to stop racism is by changing their own attitude.

Although “race” is widely accepted all over the world I believe it’s only because scientists have failed to teach the public of the true concept and biology of “race”, but once the public becomes more informed I believe that a world without race can become a reality.

Why do people judge each other based on the color of their skin? Does your skin color determine your intellectual ability? Can you identify the skin color of a person from their genes? What do you think a world without race would be like?  Are you surprised by the following video?

Photo by Here's Kate; The ability to tongue-roll is an inherited trait. Can you tongue-roll? Can your parents?

Here are a couple of websites to help you practice analyzing pedigrees.  When you’re attempting to answer these problems you must first answer the following questions:

a) Is this a sex-linked trait or a non-sex linked trait?

b) Is this a dominant trait or a recessive trait?

• Analyzing pedigree images
• Creating a pedigree
• Analyzing pedigree images
• Analyzing pedigree images

Photo credits: Doug Blane

Have you ever wondered why some people seek thrills? Or what makes people act this way?  Recent studies, such as the one described in this article, have shown that the reason for said behavior may be hidden in your genes.

Jaime Derringer has been testing specific genes with mutations that are related to the neurotransmitter dopamine that, in other studies, has been paired with thrill seeking tendencies or disorders. Derringer held a study of 635 people who had addiction problems, addiction is a sign of severe thrill seeking, and tested to see what genes in these people could be directly linked to thrill seeking. Out of 273 mutated genes that she tested, Derringer was able to narrow these down to 12 mutated genes that could be major links to thrill seeking tendencies. Just fewer than four percent of the twelve combined mutated genes explained differences in people thrill seeking.  Although Derringer has discovered fascinating new information about the mutated genes people have that cause these sometimes harmful thrill seeking tendencies, not enough is known for people to get tested for the mutated genes.

In this video, a newscast talking about how genetic mutations can cause criminal behaviors as well as anti social tendencies. Looking at the personality traits along with the DNA collected from a case study of base jumpers and criminals, the forensic psychiatrist believes that there is in fact a connection between thrill seeking and your genetics.

Do all people with these mutated genes become addicts or criminals? Do you think early detection of this mutated gene could help prevent future problems? Is the mutated gene the only cause for addiction and criminal behavior?

Photo by Chromalux

Many animals have a type of mating call which attracts the female to them in order to mate.  If a female is attracted to a charismatic male and they produce offspring, would their offspring be attractive as well?

Scientists have been searching for evidence to be able to determine if attractiveness could be hereditary. To do this, scientists in England used the Drosophila simulans fruit fly. In this species, the female is attracted to the male by their personality and flirtations.

What kind of personality and flirtations? Well, the Drosophila male flies sometimes have a “courtship song” or a mating song that attracts the female to the male. The way that they produce these “songs” is by the movement of their wings. Certain patterns and pulses produce different types of “songs”.

Another way that makes the males attractive is the pheromones that are produced.  Pheromones are sometimes sex-specific and are released by certain glands or cells to trigger the behavioral response of the opposite sex of the same species. Specialized sensory structures or cells recognize pheromones.  The neurons are thought to be responsible for the detection of pheromones in Drosophila.

The scientists paired the males and females together and looked at the average time it took them to mate. By using common sense, if they mated quickly, such as 5 minutes, then they concluded that those males are attractive to the females. If it took a longer time to mate, then most likely they do not have as much charisma as the other flies.

The offspring (sons) of the flies were paired with single females. They repeated their step in observing the amount of time it took them to mate. Just like the scientists thought, the attractive males that they started with, in fact, DID produce attractive sons!

After seeing this, scientists wondered if this same idea could be spread across to all species.  Does this mean attractiveness is hereditary in other insects or species as well?

David Hosken, an evolutionary biologist who worked on the study said, “Extrapolating from one species to another closely related species should be done with caution. Knowing lots about one species may tell you little about another.  We must remember this when we make hypotheses of other species.”

Is this kind of attractiveness shown in Drosophila also hereditary in humans?  What similarities do you notice between Drosophila and humans? Do you think it’s impossible to pull predictions about our species from Drosophila?

Jackie (the author of this post) examines a sample of anesthetized Drosophila melanogaster!

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