Question

Consider a cell of a teratoma and a healthy human epithelial (skin) cell. Now consider the DNA and the three types of RNA (mRNA, tRNA, and rRNA) found in both. For each of these (DNA, mRNA, tRNA, and rRNA), compare what you would expect to find in both a teratoma and a healthy cell. Would they be the same, or different, or both? Provide examples and explain clearly.

Answer 1

As per the question we are comparing a teratoma and a normal skin cell. One assumption we will take that both the cells were taken from the same individual organism.

In the case of DNA, we will see that both the cells have the same DNA content as they belong to the same individual. So they would be identical in nature.

In the case of tRNA and rRNA, we will notice that they are both present in equal numbers and similar types (or as required for that specific tissue location). They have their roles in DNA replication which goes unhampered in a normal skin cell also in the teratoma.

In the case of mRNA, we will see a difference in the amount in both the cells. If both the cells have different tissue of origin then they will have different types of expression of mRNA but as skin cell is a normal cell and teratoma is a tumor cell, therefore, they will have a difference of gene expression of certain genes which will have a difference in the amount of the mRNA in those cells.

For example, some tumor-suppressing genes in the teratoma will be under-expressed while many other genes responsible for the production of the tumor will be overexpressed. This will bring a net change in the value of expression of genes in both cells.