Epigenetics: Is Your DNA Your Destiny?

Thinking of getting one of those DNA testing kits?  Aside from the Ancestry tests, the tests for your  future health risks may be questionable and at this point you may want to save your money. Here is why.

Is Your DNA Your Destiny? 

The Short Version

Gene Expression: the process by which a cell converts the genetic code into RNA and protein

Epigenetics: the study of heritable changes in gene function that occur without a change in the DNA sequence

To fully illustrate the epigenetic process, one must tell the story of the agouti gene.

Both these mice have the gene that tends to produce fat, yellow pups. The mom of the brown mouse was fed B vitamins which silenced the gene. This produced  brown pups with normal appetites resulting in a thin, healthy mouse.

Without altering the genomic structure, agouti moms were then able to produce healthy brown pups of normal weight and less prone to diabetes.

How did this occur?  Some nutrients silence genes by providing methylation (adding a methyl group (CH3); others activate genes by inhibiting methylation. The B vitamins acted as methyl donors that caused methyl groups to attach more frequently to the agouti gene in utero, inhibiting its expression.  Silence or inhibiting depends on what the gene does: e.g., silencing a gene that stimulates cancer growth is beneficial; silencing a gene that suppresses cancer growth would be harmful.

 

The Longer Version: 
HERE.

Is Genomics the Future?

The Human Genome Project was completed in 2003 that identified all of the genes in the human body.

The new field of Nutritional Genomics suggest that lifestyle factors influence how nutrients influence gene activity and expression.

Although genetics can play a sizable effect on our future, lifestyle factors and the environment can often play a role in the outcome (expression). As you can see, epigenetics may  show us that genes alone are not necessarily our destiny.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

The Obesity Epidemic: Nature or Nurture?

Fat shaming is found in many aspects of our culture. The obese are described as fat and lazy and looked upon with disdain by even some of the health professionals they seek out to solve many of their health care needs. Perhaps we need to examine the complexities of the interactions that may have contributed to this so-called obesity epidemic to gain a better understanding of what the obese population has to contend with.

In 1960, only 13.4 % of Americans were overweight or obese. By 1990, about 23% were obese, and today, only two decades later, almost 36% are obese. Obesity affects both men and women and all racial and ethnic groups. As far as we know, we still had the same genes and physiology during these decades; however, the food environment or culture had obviously changed.

“The interplay between genetics and lifestyle is often illustrated by the higher incidence of obesity in Pima Indians living in Arizona than in a genetically similar group of Pima Indians living in Mexico. When this genetic susceptibility is combined with an environment that fosters a sedentary lifestyle and consumption of a calorie dense diet, the outcome is the strikingly high incidence of obesity seen in this population. The Pima Indians of Mexico are farmers who work in the fields and consume the food they grow. On the other hand, the Arizona Pima eat the high-calorie, high-fat processed foods,  found in the Standard American Diet (SAD) and lead a more sedentary lifestyle. Both groups have  higher rates of obesity due to their genetic susceptibility; however, the average BMI or the Mexican Pima is significantly lower than that of their American counterparts.” Smolin and Grosvenor, Nutrition: Science and Applications, Third Edition.

Check out my previous post HERE.

CLICK HERE.

Obesity and Willpower?

DNA and Epigenetics

It is becoming more apparent that the global obesity epidemic is due to many complex interactions between our genetic makeup, physiology  and environmental factors such as availability of cheap food, an abundant food supply and the types of foods we eat.  This interaction is referred to as epigenetics and discussed in a previous post HERE.

CLICK HERE.

 

The Real Side of Monsanto?

Monsanto is often accused of being a monster company when it comes to production of pesticides. The following articles tell both sides of the controversy surrounding this company. Interesting! What can we believe about their actual agenda?

CLICK HERE.

CLICK HERE.

 

 

GMO Foods – Hard To Avoid?

An overview of the structure of DNA. (Photo credit: Wikipedia)

 

An interesting article on genetically engineered crops around the world along with the pros and cons. This debate will continue until one side is proven right or wrong thus, it is difficult to find an unbiased article on this topic.  Both sides have legitimate arguments.  Often there is little clarification as what sets genetic engineering apart from all other types of crop improvements like selective cross breeding.  Simply put, genetic engineering involves transferring genetic material from one organism into the genetic material of a completely unrelated species, e.g. inserting a bacterial gene or DNA into a plant like corn.  In  selective cross breeding, crosses involve only organisms that are already closely related, e.g. two varieties of corn.

CLICK HERE.

Why are our Children Fat?

IS IT NATURE OR NURTURE?

A recent study examined whether our current problem with with overweight and obese children is a result of genetics or lifestyle.  Researchers at the U. of Michigan  surveyed 1000 obese six-graders.  The study was published in the American Heart Journal.

Here is what they found:

• 58% of obese children had watched two hours of TV the day before compared with 41% of non-obese children.
• 45% of obese kids always ate school lunch compared to only 34% of nonobese students.
• Fewer obese kids exercised regularly, took P.E. classes or participated in sports.

Overall, all the students, both obese and non-obese had unhealthy habits.

• More than 30% of them had consumed regular soda the day before the survey.
• Less than one-half reported eating two servings of fruits and vegetables within the past 24 hours.
• One third of them said they exercised for 30 minutes for 5 days in the previous week.

Bottom Line:  The results suggest that although genetics in some cases is a factor, it appears that lifestyle factors play a significant role in most.  It also could be a combination of the interaction between the two.  In future posts, emphasis will be on the school lunch aspect of this study.  How do our school lunches compare with those found in other countries?