Honey, could you please stop smoking? The money we spent every month on buying your cigarettes is enough for the family to travel overseas!
Hey, you’re exaggerating! Didn’t we just come back from Rhode Island, right? Come on, it’s no big deal. Why make a fuss about it?
Rhode Island is just like, what, 30-minute drive away…? Alright, I know I’ll never win you on this, but I bet your “bodily shoelace caps” are way shorter than those who don’t smoke. And probably, they’ve worn out bad. Be careful, your DNA might be slipping away!
My what? “Bodily shoelace caps”? What are you talking about? I’ve only heard of shoelace caps on my shoes. Oh, I get it! You want to scare me off on smoking. Fine, just use the cancer approach or something, but my genes? Come on, you’re being absurd!
Daddy, mommy is not trying to scare you actually.
We each have over 30 trillion cells inside our bodies, among some of which contain a nucleus that serves as hereditary and metabolic functions. This cell nucleus is where our precious 23 pairs of chromosomes are held which in turn store the genes with our DNA (deoxyribonucleic acid).
So? What do these have to do with my “bodily shoelace caps” and DNA loss?
See? Told you to read more and smoke less! Now you know.
At the two tips of each chromosome are telomeres that look very similar to shoelace aglets. That’s why scientists like to call them the “internal/bodily shoelace caps”. Besides from its close appearance to shoelace aglets, the function of telomeres are also very much alike shoelace caps, that is, to protect the DNA within the chromosomes (Wood, 2016). These telomeres are very helpful during regular DNA replications as they protect our genes from fraying and losing away. In this case…
Wait, why does our body replicate our own DNA? Where would these replications go? Clones?!
Dad, just imagine your body as a computer, that data would be produced and collected through a long time span, causing the computer to go slower and slower. This doesn’t mean that we just throw away the computer; instead, what we normally do is to replace the old processor or memory chip with a new one. Now, consider the same thing for human bodies. As we age, more cells will be divided and produced. Yet, during each cell division, aka. mitosis, the older cells will lose some of their organic hereditary constituents. To avoid losing the capability to reproduce new genes, human bodies automatically perform a DNA replication process in which old DNAs are replicated and later replaced by new ones (YourGenome, n.d.). Normally, around 50-250 pairs of DNAs would be lost during this replication process, which makes the “internal/bodily shoelace caps” that protect our DNAs even more valuable (LearnGenetics, n.d.).
Okay, so what you are saying is that whenever my body undergoes a mitosis for the sake of heredity, the telomeres that wrap my DNAs within my chromosomes will do whatever it can to prevent huge losses of my DNAs, right?
Yes! Oh, honey, you seem to have grown smarter! Once too much DNAs are lost, the risk of getting cancer-related diseases spikes up as well (Huzen et al., 2014). What’s more, according to a recently published research, it is found that smokers are more likely to have shorter telomeres compared with non-smokers (Bateson et al., 2019), though it doesn’t directly imply a cause-and-effect relationship between smoking and shorter telomeres. Yet, more and more studies are pointing at the significantly shorter lengths and lifespans of telomeres found among frequent smokers which may reach to approximately three times less (Huzen et al., 2014; Wang et al., 2018).
(Nodding) That’s also why cancer, cardiovascular diseases, Alzheimer’s disease, and other aging-associated diseases are more likely to happen on smokers (Huzen et al., 2014; Wang et al., 2018). It also seems to suggest why one is more likely to die young when his/her telomere are found relatively short (Zgheib et al., 2018).
This…is…just insane! I’ve already given up my money and health to this little tube, and I can’t believe it’s asking for more! My DNAs! Not even a chance for my inheritance…
Scared? Then what are you waiting for? Vote tactically: One for shoelace and none for cigarette!
- Bateson, M. et al. (2019). Smoking does not accelerate leucocyte telomere attrition: A meta-analysis of 18 longitudinal cohorts. Royal Society Publishing, 6, 1-16. Retrieved from https://royalsocietypublishing.org/doi/pdf/10.1098/rsos.190420
- Huzen, J. et al. (2014). Telomere length loss due to smoking and metabolic traits. Journal of Internal Medicine, 275, 155-163. doi: 10.1111/joim.12149
- LearnGenetics (n.d.). Are Telomeres the key to aging and cancer? University of Utah. Retrieved from https://learn.genetics.utah.edu/content/basics/telomeres/
- Wang, Q., Zhan, Y., Pedersen, N. L., Fang, F. & Hägg, S. (2018). Telomere length and all-cause mortality: A meta-analysis. Ageing Research Reviews, 48, 11-20. doi: 10.1016/j.arr.2018.09.002
- Wood, M. (2016, November 17). Smoking and its effect on telomeres, the shoelace caps of your DNA. UChicago Medicine. Retrieved from https://www.uchicagomedicine.org/forefront/biological-sciences-articles/2016/november/smoking-and-its-effect-on-telomeres-the-shoelace-caps-of-your-dna
- YourGenome (n.d.). What is DNA replication? Retrieved from https://www.yourgenome.org/facts/what-is-dna-replication
- Zgheib, N. K. et al. (2018). Short Telomere length is associated with aging, central obesity, poor sleep and hypertension in Lebanese individuals. Aging and Disease, 9(1), 77-89. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5772860/pdf/ad-9-1-77.pdf