“Started from the bottom, now we here” is more than just a catchy Drake hook that youth twerk to in the club; it is a sentiment echoed throughout rap and hip-hop culture. From The Notorious B.I.G. to Eminem, rap music celebrates rags-to-riches stories that trace a persons ascent from crushing poverty to enormous wealth and icon status.
While the majority of rap songs focus on money, these recording artists may actually be improving more than their financial situation as they climb the rungs of the social class ladder—they may actually be improving their health. Research conducted with rhesus monkeys suggests that music moguls and laypeople alike may enhance their long-term health by moving up in the socioeconomic hierarchy, which alters regulation and expression of immune system-related genes.
We've known for a while that health is irrevocably tethered to socioeconomic status. The well-known Whitehall study was the first of its kind to definitively demonstrate this link. Surveying 18,000 British civil servants ranging in occupations from messengers to high-ranking government officials, the study concluded that men in the lowest grades of employment have higher mortality rates compared to those working at the top of the career totem pole. Additional studies have shown that lower social classes are more vulnerable to asthma, cancer, cardiovascular disease, diabetes, and infectious diseases.
This socioeconomic-health gradient, where those with better social standing tend to be healthier, exists among a quagmire of environmental and biological influences that affect the homeostatic balance. Income, diet, physical activity, education, and access to healthcare can account for a portion of the health disparity observed in developed countries but they do not encompass the whole picture. To address the unaccounted for effect of social status on disease risk, researchers have begun to look for answers in DNA.
Duke University scientists studied female rhesus monkeys to understand the how dominance rank—the primate correlate to human social status—altered gene expression. Previous work in this species has demonstrated that low dominance rank can lead to negative changes in the stress-response. In this study researchers wanted to see if there was an underlying genetic cause for these stress-related changes.
Social hierarchies were constructed by introducing female monkeys into new social groups. Members that joined the group earlier held a higher dominance rank. Scientists then collected white blood cells, which are involved in the body’s immune response, from the monkeys and analyzed them.
When subjected to a stressful situation, females with lower dominance rank had a slower glucocorticoid response, a commonly used measure of physiological stress that is known to influence the immune system. Additionally, levels of T cell-type white blood cells were decreased creating a potential immune vulnerability.
Researchers also found that the DNA expression profile in white blood cells could predict the social rank of an animal with 80 percent accuracy and that rank was highly correlated with changes observed specifically in immune gene expression.
Across dominance groupings DNA-methylation, which is an epigenetic DNA modification that changes the ability of a gene to be turned on or off, was altered according to rank in a reversible fashion. When a female changed rank order, gene expression levels were adjusted. For example, the DNA signature of a low ranking female that moved up in the hierarchy changed to resemble that of other high ranking females, suggesting these modifications are impermanent.
As it turns out Canadian rapper Drake's rags-to-riches tale is just that: a story. In fact, he attended an affluent Toronto high school and starred on the television series Degrassi: The Next Generation. However, if he had had truly “started from the bottom” like his song suggests, he may have improved his health status through subtle changes in his gene expression upon arrival at the top.
photo by markhoekstra