It has been known for some time that people who come from families in disadvantaged environments are more prone to getting sick and ultimately dying from disease. What isn’t known is why these people are getting sick. Is it because they are exposed to more toxins or infectious agents? Or is their environment some how affecting their DNA? Many times in research, we use the term socioeconomic status to describe people who have either low income, low education or poor employment (1). These people would generally be described as the lower class and may be living in or just above the poverty line. Now, recent research shows that these people may suffer health effects from living in these conditions on a DNA level (2).
DNA is organized within the nucleus of cells into structures called chromosomes. Humans have 46 chromosomes per cell (not including the reproductive sperm and eggs) and the chromosomes are protected by a cap at either end known as a telomere. You can think of a telomere like the sole of a shoe. The sole protects your foot from the rough ground but over time the sole wears away and becomes thinner and thinner. Telomeres protect the DNA of cells from damage to the important genes within the DNA but over time this protection is worn away. Every time the cell divides the telomeres get a little shorter. Short telomeres have been linked with diseases like cancer and dementia as well as aging. In this recent study, the researchers showed that 9 year old boys growing up in environments with low income, low parental education, unstable family structure (divorce and violence for example) or with harsh parenting have significantly shorter telomeres than those who grew up in more favorable environments. What does this mean? Well it is possible that in the future these boys could be prone to developing diseases that are linked with shorter telomeres such as cancer, dementia and old age related disorders. Since telomeres do not regenerate normally over a person’s lifetime (with the exception of stem cells or cancer cells) this means that how children are raised could impact their health for years to come.
This study lends evidence to the constant question of how the environment can impact health and how the environment interacts with someone’s genes. This study showed that some individuals are more prone to being affected by their environment (whether it is a poor one or a good one) and that this susceptibility can be genetically determined. Since many diseases that we battle are a mixture of genetic factors and environmental factors, this study helps to connect the two factors to each other. Further research should be done to determine how socioeconomic status affects females and those of differing ethnicity. Research such as this goes a long way to show that poverty is not only a economic problem but also a health concern and will hopefully help to one day develop policies that will see the end of poverty.
1. Adler NE, Ostrove JM (1999) Socioeconomic status and health: What we know and what we don’t. Ann N Y Acad Sci 896:3–15.
2. Colter Mitchell, John Hobcraft, Sara S. McLanahan, Susan Rutherford Siegel, Arthur Berg, Jeanne Brooks-Gunn, Irwin Garfinkel, and Daniel Notterman. Social disadvantage, genetic sensitivity, and children’s telomere length. PNAS 2014. http://www.pnas.org/content/111/16/5944