You have just finished an exhausting genetic screen You now

You have just finished an exhausting genetic screen. You now want to fully characterize one new mutation you are calling mtp. You need to determine if the mtp mutation is a nullomorph, hypomorph, or hypermorph. Describe multiple types of experiments you would perform to fully characterize this new mutant (number them for clarity) AND describe your interpretation of possible results for each experiment using the following type of sentence structure/ logic:   If I do __ and see _____, then I will conclude_______. In contrast, if I see____, then I will conclude ___________)

Solution

A nullomorph mutation can be defined as the one which has no change in physiological function or has not relevant functional capacity. A hypomorph mutation can be defined as the one which decreases the gene expression and hence dampens the physiological expression. On the other hand, hypermorph mutation can be defined as the one which causes increase in genetic expression and hence physiological appearance of gene product.

Experimental design: Consider a cell line which is supposed to have mutation for enhanced expression of mtp on its plasma membrane. In order to analyse the expression levels and nature of mutation, a simple immunofluorescence experiment can be designed in given way:

Observations: Change in expression levels of mtp direclty correlates with changes in its fluorescence intensity in two experimental groups. Suppose that the mutated cells show high intensity of mtp expression as compared to control cells. This clearly suggests up-regulation in gene expression of mtp hence resutls in a hypermorph mutation.

Thus, the logical filling of the sentence will be:

If I do controlled exprements with two experimental groups and see changes in gene expression in terms of intensity of immunoflurescnce, then I will conclude changes in expression levels as hypermorph or hypomorph. In contrast, if I see no change in intensity of immunoflurescence, then I will conclude that the mutation is a nullomorph.