What does it mean to have “good” genes? You hear it in everyday conversation all the time: “My dad lived until his 90s, I hope I got his genes!” or “I have good genes, I can eat whatever I want and I still stay skinny!” Some recent news articles have even posited that “good genes” are evident in attractive people, or people with symmetrical features. In reality, it’s a little bit more complicated than that.
What Are Genes?
Genes are basically DNA, the entire code and source of information that defines, well, you. You have two copies, one from each parent. Together, these copies are expressed as proteins, which are the building blocks of the tissue and cells that make up your body. The different combinations of these copies can create different effects when they’re expressed.
So Are There Good Genes and Bad Genes?
It’s not quite that simple. Let’s look at the APOE gene, one of the most widely studied genes in the scientific field. It has multiple copies, also known as alleles. One copy, the APOE E4 is known for helping the absorption of lipids in our intestines and efficient storage of fat in the body tissue. But it’s also been associated with high rates of cholesterol and increased risk of heart disease. APOE E4 is also gaining a reputation in the scientific world as a risk factor for Alzheimer’s. On the other hand, the other copy, APOE E3, is better for the meat-based and fat-rich diets that most people eat today. People with at least one E3 copy are more likely to have lower serum cholesterol, lower risk of coronary artery disease, decreased cognitive decline, and they live an average of 6 years longer than E4 carriers. When compared to each other, E3 is the “good” gene.
Not That Simple
However, genes also have to be measured against what environment they’re in. Sickle-cell anemia is a genetic disease of the blood that actually gives the carrier protection against malaria, so in an environment rife with malaria, a person with sickle-cell actually has an advantage. But in an environment with little oxygen in the air, like at high altitudes, the sickle cell gene can be detrimental.
What Genes Define Youth
Some studies have shown that up to 60% percent of what contributes to facial aging is due to genetics. Today, scientists are studying genes like the p16INK4a in mice and the ELT genes in nematodes to see if the effects of aging can be reversed. In the future, scientists hope to find the equivalent genes in humans to be able to control the aging process. For now, they’re studying the MC1R gene, which has a specific copy that allows carriers to look much younger than their age.