By: Meenu Johnkutty ’21

The need to sleep is one of health and medicine’s biggest paradoxes. Though we spend nearly a third of our lives asleep, little is really known about this process. According to the American Academy of Sleep Medicine, over 30 to 35% of the population suffers from insomnia, which is characterized by a difficulty in initiating or maintaining sleep throughout the night. As Americans sleep less and less every year, more attention is being shifted towards demystifying the need to sleep and how much sleep Americans really need every night.  

One study released by the National Institute of Health is bringing us a step closer toward unshrouding this mystery. Scientists from the National Lung, Heart, and Blood Institute recently investigated differences in a group of genes which may explain why some people need a lot of sleep and why some people may not need as much.

The researchers artificially bred 13 generations of wild fruit flies in order to create populations of flies that were either long-sleepers or short-sleepers. Instead of engineering mutations within a sample mutation to express a particular gene, the researchers created an artificial breeding program which allowed natural variations in sleep duration to express itself in the population. The researchers found on average, a 9-hour difference in sleep duration between long and short sleepers in the fly population. The researchers found 126 differences among 80 genes associated with sleep duration between the long and short sleepers. Additionally, the scientists identified differences in allele frequency between the two groups of sleepers, finding differences in developmental and signaling pathways. This implicates a variety of different factors which affect sleep duration, suggesting that sleep may be more complex than originally thought.

Interestingly, the researchers did not find any differences in the average lifespan in the short and long sleepers. This suggests that there may be little physiological consequences to being an extremely long or short sleeper. More research is needed in order to determine if being a short or a long sleeper has other effects on humans.

References:

1. S. T. Harbison, et al., Selection for long and short sleep duration in Drosophila melanogaster reveals the complex genetic network underlying natural variation in sleep. PLOS Genetics (2017). doi: 10.1371/journal.pgen.1007098.
2. Image retrieved from: https://www.pexels.com/photo/alarm-clock-analogue-bed-bedroom-271818/