Human Health – BioQuakes

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Obesity has become an increasingly prevalent epidemic around the globe and especially in the United States. Obesity has numerous roots. Recently, researchers from the McGill Centre for the Convergence of Health and Economics found that in some circumstances, it is possible to blame obesity not solely on genetic make-up, but rather on genetic make-up and socio-economic background combined. The McGill researchers discovered that the fat intake of a female who is a carrier of DRD4 VNTR with 7 repeats, a specific gene variant, is determined by the interaction of the female’s socio-economic environment with the gene. This gene variant affects about 20% of the population and is commonly related to obesity, especially in females. Males are typically not as affected by the gene because when comparing males and females at the same age, males do not typically show the same pattern of food preferences.

In order to research this topic, McGill researchers randomly selected about 200 Canadian children with an average age of 4 from the MAVAN birth cohort in Montreal, Quebec and Hamilton, Ontario to take place in the experiment. The McGill researchers used food diaries kept by the parents of every child in order to determine what was being eaten and how often the child was fed. The researchers were able to calculate the percentages of fat, protein, and carbohydrates the children were consuming, as well as the BMI of every child. Since the children were selected at random, the researchers tested every child for the gene variant using a saliva test. The researchers also analyzed the socio-economic background of every child and availability of particular foods based off of the family’s income.

Laurette Dubé, Scientific Director at this particular Centre at McGill and lead researcher on the study, analyzed the results. Dubé found that when comparing two females from the same socio-economic background, one with the gene variant and one without, the female with the gene variant had a higher fat intake, even though the two females came from the same socio-economic background. She also discovered that when comparing two females with the gene variant, one coming from a wealthy family and one coming from a poor family, the female coming from the poorer family had a higher fat intake, despite the fact the two females were both carriers of the gene variant. This newly found research led the McGill research team to believe that the gene alone does not determine an individual’s fat intake, but instead the gene causes an individual to be more sensitive to his or typically her environmental conditions that determine what are “good” eating patterns and what are “bad” eating patterns. Dr. Robert Levitan, co-invesitgator on the project, leader of the childhood obesity program of the MAVAN cohort, and Senior Scientist at the Centre for Addiction and Mental Health (CAMH), is an expert on the DRD4 gene in adult female “overeaters”. Levitan said, “We previously assumed that the 7-repeat variant caused weight gain in these patients by increasing the rewarding aspects of certain foods. These new results suggest a different way that the gene might affect food choices” (Biology News).

In certain cases, obesity isn’t all about genetic make-up, but the likeliness of obesity is determined by the socio-economic background of an individual as well! So, if you are a carrier of the DRD4 VNTR with 7 repeats gene variant, which, because of your environment, impacts your decisions, is it really your choice to make better choices?

Source: Biology News

Does long-term endurance training impact muscle epigenetics?

By mitokahndria

On March 8, 2015

In Student Post

Epigenetics translates to “above” or “on top of” genetics. To be more specific, Epigenetics is the study of how modification of gene expression can cause changes in many organisms.

A new study from Karolinska Institutet in Sweden explores the theory that long-term endurance training alters the epigenetic pattern in the human skeletal muscle. The team that conducted the research also explored strong links between these altered epigenetic patterns and the activity in genes controlling improved metabolism and inflammation.

The study was conducted using 23 young and healthy men and women. The men and woman would perform one-legged cycling – where the untrained leg would be the control of the experiment. Four times a week and over the course of three months, the volunteers would participate in a 45 minute training session. Though skeletal muscle biopsies, supervisors would measure their markers for skeletal muscle metabolism, methylation status of 480,000 sites in the genome, and activity of over 20,000 genes.

At the end of the study, the researchers concluded that there was a strong relationship between epigenetic methylation and the change in activity of 4000 genes in total. Epigenetic methylation is defined as the “addition of a methyl group to a substrate or the substitution of an atom or group by a methyl group. ” Moreover, it was determined that methylation levels increased when involved in skeletal muscle adaptation and the metabolism of carbohydrates. However, methylation levels decreased in regions associated to inflammation.

Furthermore, Carl Johan Sundberg found that “endurance training in a coordinated fashion affects thousands of DNA methylation sites and genes associated to improvement in muscle function and health.” He believes that this determination could be vital to understanding the treatment of diabetes and cardiovascular disease as well as how to properly maintain good muscle function throughout life.

This article relates very much to our work in class as we learn the Molecular Genetics Unit. It connects because we are learning what happens when mutations occur in one’s genome and the impacts those mutations have on someone. For example, cancer is one of the most researched and explored topics in regard to how modification of gene expression alters organisms. Oncogenes and Tumor suppressor genes have vital impacts on cellular division, changes to cellular function, and the growth of tumors.

Human Health in the Hands of a Naked Mole Rat?

By lp719

On October 16, 2011

In Student Post

Our genome is similar to that?!

What do you think of when you see a naked mole rat? Do you think it is hideous because it has no fur? Do you think you would want to pet it? Whatever you think about this animal, you would never expect that it could improve human health. Who knew they could be the key to increase the human life span? Yep, that’s right! Naked mole rats, as ugly as they may be, are now considered extremely helpful and important in designing treatments for fatal diseases.

A recent study discovered that the newly deciphered genome of the naked mole rat could help researchers learn more about evolution and even help design better treatments for diseases like cancer and stroke. Scientists believe that this genome will help decipher the naked mole rat’s unique traits, behaviors and social characteristics.

Scientists who deciphered the naked mole rat’s genome used shotgun sequencing to read it. The naked mole rat was raised in a lab and once it was an adult, the scientists studied its genome. They read long sequences of the nucleobases that make up the rat’s DNA and then lined them up to find where they overlapped. Once they read the complete genome, the researchers compared it to the genomes of humans and mice.

The researchers found multiple mutations in the naked mole rat’s genes that correlate to its characteristics. They found that the rat had turned off several genes related to vision because they live in the dark. They also saw a mutation in the gene that functions in hairlessness, which explains why these rats are bald. Naked mole rats live in low-oxygen burrows and stroke and heart attack deprive parts of the body from oxygen. By comparing the genome of the naked mole rat to the human genome and discovering how they survive in this type of low-oxygen environment, scientists can design more effective treatments to improve diseases that deprive the body of oxygen. The researchers sequenced the whole genome and will make it available free online, so groups that study genes involved in cancer and longevity can compare those genes to the mole rat’s genome. You can even look it up online and determine for yourself which genes you think are similar to ours!

This new information about the naked mole rat’s genome can be extremely helpful for treatments that could increase the human life span and improve human health. Who knows, maybe the deciphering of the genome could even lead to find the fountain of youth! What do you think? Do you think the rat’s genome is similar enough to ours that scientists can design more effective medication for diseases? How far do you think these researchers are able to go? If you are unsure, just be sure of one thing, the next time you see a naked mole rat, be sure you look at it with a different perspective because in twenty years that very rat’s genome may lead to the cure for cancer!

BioQuakes

AP Biology class blog for discussing current research in Biology

Tag: Human Health

Is it Really Your Choice to Make Better Choices?

Does long-term endurance training impact muscle epigenetics?

Human Health in the Hands of a Naked Mole Rat?

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