Question

What are aneuploidy and tetraploidy in cancer cells?

Answer 1

Mutations:

1. The change or alteration in the DNA sequences results in changes in the phenotype and genotype of an organism is called a mutation.
2. The change in the DNA is caused due to change in the single base pair of the DNA (point mutation) or exposure to the chemicals that can cause mutations (mutagens).
3. The mutations can occur both in the somatic and germinal cells (sex cells) of the body.
4. Types of mutation: Somatic mutation and Germinal mutation.
5. Somatic mutation: The mutations that occur in the somatic cells of an individual are called somatic mutations.
6. Germinal mutation: The mutations that occur in germ cells (sex cells) of an individual.

Aneuploidy:

1. The chromosomal abnormality is caused due to abnormal chromosome numbers in cells.
2. The abnormal chromosome number is due to the presence or absence of a chromosome.

Tetraploidy:

1. It is a type of polyploidy (chromosomal abnormality) in which the single cell has 4 sets of chromosomes.

Cancer :

1. The unregulated growth of cells forming a tumor is called cancer.
2. Cancer is caused due to genetic mutations in the cell which can pass from one generation to the next generation.
3. However, exposure to chemicals and harmful Ultraviolet rays, intake of tobacco, and alcohol are cancer-causing agents (carcinogens).
4. Cancers can benign (a particular tumor is localized at a particular location of the body, which does not spread to other body parts) or malignant (a tumor that quickly grows in blood and from it spreads to different parts of the body).

Result of Aneuploidy in cancer :

1. Aneuploidy is caused due to gain or loss of chromosomes, when the parent cell divides each daughter cell receives an abnormal number of chromosomes, which disrupts cell division, leading to tumorigenesis.

Result of Tetraploidy in cancer:

1. Tetraploidy is the type of polyploidy in which the single cell has 4 sets of chromosomes, which is caused due to failure of cytokinesis during cell division, and viral-induced fusion.
2. Tetraploidy facilitates chromosomal instability (CIN), that is the elevated level of chromosomal gain and loss which can cause the production of aneuploid cells carrying structural and numerical aberrations of chromosomes which ultimately causes tumorigenesis.