Your Genes And The Environment You Live In

What Are "Genes"?

Inside your cells, there are 23 pairs of chromosomes that carry your genetic information. You received one set of chromosomes from your mother and one set of chromosomes from your father. Each chromosome is made up of two long strands of deoxyribonucleic acid (also known as DNA). The two strands connect such that the chemical letters, also known as nucleotides, on each strand pair up. The many combinations of the four nucleotides in DNA (adenine [A], thymine [T], guanine [G], and cytosine [C]) spell the language known as your genetic code.

There are more than six billion nucleotide pairs in your DNA, some of which accounts for your genes. A gene can be defined as a sequence of nucleotides that controls one or more particular characteristics you received from your parents. Genes influence your physical traits, the likelihood of suffering from a specific disease or health condition, and the way your body responds to the environment you live in.

What is a "SNP"?

All humans are similar for 99% of the same genetic code. So what makes you different from everyone else? Single nucleotide polymorphisms, or SNPs (pronounced "Snips") , make up some of these differences. These are variations in the nucleotides on certain genes. For example, a portion of your genetic code may be AATGCCAG while the same portion of your neighbor’s code may be AATGCCCG. This SNP is one of the things that make you different from your neighbor. There are over 12 million SNPs throughout each of our genomes. Scientists have now developed technology that can use these SNPs to discover genetic regions that have an effect on the likelihood that a person will develop a trait or disease.

What Is a "Trait"?

A trait is a characteristic that is passed down from your parents through genes. Traits describe characteristics such as eye color, weight, or the presence or absence of a disease or condition. One gene or multiple genes can determine what traits you will have. As an example, your eye color depends on what genes were passed on to you from your parents and the combination of SNPs in those genes.

What Does "Environment" Mean?

While your genes are something inside your cells that you get from your parents, your environment is the forces outside your body that affect whether or not you will develop a particular trait or disease. Simply having a specific gene does not determine whether or not you will get a specific trait or disease. There may be environmental factors that play a role in determining whether or not you will develop a specific trait or disease. For example, you may have genes that indicate that you have a high risk of developing diabetes. However, if you exercise regularly, keep your weight under control, and make healthy lifestyle choices, you can effectively control your environment and reduce your risk for developing diabetes. As a result of controlling your environment, even if you have the “diabetes gene,” it is possible that you may never develop diabetes.

How Are Your Genes & Environment Related to Your Traits?

Together your genes and your environment interact to determine your traits, or the characteristics that describe you. The debate surrounding whether genes or the environment plays a larger role is sometimes referred to as “nature versus nurture.”

This concept can be illustrated by thinking about weight. You may have inherited the gene (or genes) from your parents that indicate you have a chance of becoming obese. Even if you are not obese, knowing that you are at a higher risk of becoming obese may encourage you to talk to your doctor about preventative measures. Your doctor may discuss healthy eating habits, exercise routines that are appropriate for you, or other ways to control your weight. Such preventative measures may not only decrease your risk of developing obesity, but they may also decrease your risk of developing other diseases associated with obesity such as high blood pressure, diabetes, or heart disease. In this way, the knowledge you have regarding your genes will allow you to become proactive about preventing the disease (and possibly other diseases), thus using your environment to influence your traits.