The diagram shows a strand of mRNA undergoing splicing - Scottish Highers Human Biology - Question 4 - 2022

To find the number of amino acids, we first calculate the total number of bases in the mature mRNA transcript. The primary transcript had 3150 bases, and 600 bases were spliced out, so:

Total bases in mature transcript:

$3150 - 600 = 2550$

Since each amino acid is coded for by a codon (3 bases), we divide the total number of bases by 3:

Number of amino acids:

$\frac{2550}{3} = 850$

However, we must subtract 1 for the stop codon. Thus, the total number of amino acids is:

$850 - 1 = 848$

Alternative (RNA) splicing.

Alternative splicing allows for different combinations of exons to be included or excluded from the final mRNA transcript. This means that a single gene can produce multiple mRNA variants, which can each code for distinct proteins due to variations in their exon composition.

The mutation has retained an intron in the mature mRNA transcript, meaning that not all introns have been removed. This may affect the sequencing and composition of the final protein product.

The presence of the intron in the mature mRNA could disrupt the reading frame of the coding sequence, potentially leading to the production of a truncated protein or a protein with an altered shape/length. This may result in a dysfunctional protein that cannot perform its intended biological role.