The final 8 bases of the second intron (tcctttag) have been replaced with a different sequence of 6 bases (ttgtgt), deleting the splice acceptor site. If splicing failed the resulting protein would contain 92 amino acids of the normal protein, followed by a novel sequence of 36 amino acids.
The final 8 bases of the intron (TCCTTTAG) have been replaced with a different sequence of 6 bases (TTGTGT).
TTGTGT
B. Wakimoto and D. Lindsley