For the Following Gene, You Notice the Following Results What Type of Sequence Has Been Mutated in Mutant 4

Short Answer

For the following gene, you notice the following results. $$\begin{array} { l c c c } \text { Mutant \# } & \text { Deletion Region } & \text { \% Transription (lungs) } & \text { \% Transaription (kid) } \\\hline \text { WT } & \text { None } & 100 \% & 100 \% \\1 & 1 - 200 & 130 \% & 130 \% \\2 & 250 - 400 & 100 \% & 100 \% \\3 & 500 - 800 & 50 \% & 50 \% \\4 & 950 - 1100 & 0 \% & 100 \%\end{array}$$
What type of sequence has been mutated in mutant 4?