Regularly staying up late and hitting that snooze button on mornings? Well if so, you’re most likely a “night owl” and before blaming this solely on environmental conditions, it’s worth pointing out that this is also partially as a result of your genes.
Previous studies, such as that made by Aachen University a few years ago, proved that there were physical differences between those who naturally feel more awake at different times of the day. In the study they observed that “night owls” had reduced integrity of white matter in multiple areas of the brain compared to their earlier-awaking counterparts: a quality that has been linked to depression (https://www.ncbi.nlm.nih.gov/pubmed/21170955) and thought to be as a result of “social jetlag”, where someone’s biological and social time are not aligned.
Though this was proven to be not the only reason when last month the 2017 Nobel Prize for physiology or medicine went to Jeffrey Hall, Michael Rosbash and Michael Young for explaining the reason for circadian rhythm (our body clock- a cycle by which physiological processes are regulated). Whilst this process may be controlled by external factors, such as the concentration of blue light, which suppresses melatonin and so sleep as the concentration increases, the three US scientists also proved that it can be influenced by genes.
Before getting to your lie-ins, let’s first look at the experiment they did. Using fruit flies, Rosbash and Hall isolated the section of DNA responsible for circadian rhythm called the period gene, which codes for the protein PER. Over a 24 hour cycle levels of this protein vary, decreasing during the day and increasing at night, switching off its own genetic instructions as it increases (a negative feedback loop).
However, Young discovered that genes “timeless” (tim) and “double-time” (dbt) each encode proteins which have varying effects on the stability of PER. This causes an organism’s internal clock to be slower or faster when PER is more stable or less stable respectively, hence causing us to have different chronotypes (times of the day when we are naturally inclined to feel more alert or tired): some being “morning larks” (early chronotypes); others “night owls” (late chronotypes) and the rest somewhere in between (intermediate chronotypes).
So if you find yourself constantly going late to school or work because you want “just 5 more minutes” in bed, then instead of blaming the horrendous traffic- which you could have avoided by leaving on time- remember to say that you can’t help it: it’s is in your genes! (Note that whilst this may be partly due to a predisposition you have no control over, there are ways to manage it and so it’s unlikely that your teacher or boss will allow this excuse… Sorry!)