Molecular Biology Report: Telomeres, Cellular Age, Cancer, and Dolly

This report delves into the intricate relationship between telomeres, cellular aging, and cancer. Telomeres, the protective caps at the ends of chromosomes, play a crucial role in safeguarding genetic information and are linked to both aging and cancer development. The report highlights how telomeres shorten with each cell division, and how this shortening is associated with increased risks of age-related diseases and cancer. It further explores the connection between telomeres and cancer, explaining how cells with shortened telomeres may either die or produce more telomerase. The report also investigates the case of Dolly the sheep, the first mammal cloned from an adult cell, whose telomeres were shorter than expected, and the factors that contributed to this phenomenon are discussed. The report concludes by emphasizing the significance of telomeres and telomerase as key subjects in future research related to aging and cancer.

Student’s Last Name1
Molecular Biology
By (Name)
Course
Professor
University
Date

Student’s Last Name2
Introduction
Within a cell’s nucleus, the genes are aligned along with crumpled, double-stranded DNA
molecules that are referred to as chromosomes. Telomeres are the DNA stretches that are found
at the ends of those chromosomes. Their main role is to protect the genetic information and they
create an opportunity for the cells to segregate (de Jesus and Blasco, 2013 p.514). Moreover,
they keep secrets about ageing and cancer. In most cases, telomeres are described like the plastic
tips of a shoelace since they protect the ends of chromosomes against sticking or fraying to each
other to avoid scrambling or destroying the genetic data of an organism. Moreover, every time
cell division takes place, the telomeres shorten. When they cannot shorten anymore, the cell
stops dividing because either it dies, or it becomes senescent and inactive. Thus, the process of
shortening is connected to higher risks of cancer, ageing, or death.
The connection between Telomeres (Cellular Age and Cancer)
To start with, telomeres are connected to ageing because, among individuals who are
above 60 years, those with shorter telomeres were reported to be more vulnerable as they were
three times probable to succumb from heart failure and eight times to die from an infectious
illness. However, even though the shortening of telomeres is connected to the ageing process, it
has not yet been discovered if the shorter telomeres can be seen as signs of ageing such as the
grey hair or they actually cause ageing. The scientists are unsure about the relationship between
the ageing process and shortening of telomeres even though they have succeeded in using
telomerase in the lab to maintain the division of human cells beyond the usual limit yet they do
not develop into cancer (Blackburn, Epel and Lin, 2015 p.1193). On the other hand, telomeres
are connected to cancer because they divide multiple times until the telomeres happen to be too
short. In most cases, if the cells are too short they may die or at some point, they make more

Student’s Last Name3
telomerase enzyme that prevents them from being shorter (Shay and Wright, 2011 p.349).
Notably, many cancers are made of shortened telomeres such as prostate, bladder, head, neck,
kidney, pancreatic, and bone. Additionally, the estimation of telomerase can be a significant
method of detecting cancer.
Why is Dolly’s Telomeres Short?
Dolly’s telomeres are termed to be short due to various methods that were involved while
the cloned embryos were implanted and also, cultured. In this case, the enzyme that contributes
to telomeres elongation is more in the normal and healthy embryo but in case the implantation
process is inefficient or slow, it may influence the implantation process thus the embryos grow
with “old” cells rather than the totally reset (Zhao et al., 2014.p.1323). Precisely, Dolly telomeres
are short because the DNA used was obtained from an old sheep.
Conclusion
To summarize, the complicated involvement of telomeres in association with ageing and
cancer creates a platform whereby telomerase and telomeres remain significant subjects of
concern in the future. On the other hand, the argument about why dolly’s telomeres are short
needs to be revisited to provide a concrete argument.

Student’s Last Name4
Bibliography
Blackburn, E.H., Epel, E.S. and Lin, J., 2015. Human telomere biology: a contributory and
interactive factor in aging, disease risks, and protection. Science, 350(6265), pp.1193-1198
de Jesus, B.B. and Blasco, M.A., 2013. Telomerase at the intersection of cancer and
aging. Trends in genetics, 29(9), pp.513-520.
Shay, J.W. and Wright, W.E., 2011, December. Role of telomeres and telomerase in cancer.
In Seminars in cancer biology (Vol. 21, No. 6, pp. 349-353). Academic Press.
Zhao, Z., Pan, X., Liu, L. and Liu, N., 2014. Telomere length maintenance, shortening, and
lengthening. Journal of cellular physiology, 229(10), pp.1323-1329.