Question

1. You find that individuals displaying mild symptoms when infected with the COVID-19 virus are producing an alternatively spliced protein that lacks the 2^nd exon. The most likely explanation for the absence of this exon in the mRNA is which of the following?

1. The excision of introns is a random process
2. The first intron has a weak 3’ splice site
3. The second intron has a strong 5’ splice site
4. The second intron has a weak 3’ splice site
5. These individuals have a nonfunctional U6 snRNP

Answer 1

Answer will be A option.

As splicing is completely randkm process whose information is present internally to mRNA.

And that's how what is inton in one case could be exon in next case of splicing or vice verse and that's how alternate splicing work which means from one mRNA organism can make several different type of proteins.

And also RNA virus are having high rate of error as RNA replication doesnot have repair mechanism and hence RNA virus changes very fast.

Hope it's clear...thanks