ENU treatment caused a T>C substitution in intron 2, changing the exon 2-intron 2 splice donor site G-GT to G-GC. This results in alternatively spliced transcripts that uses a cryptic splice donor upstream and lack the last 51 nucleotides of exon 2, thus deleting 17 amino acids (amino acids 35-51) from the encoded peptide. This in-frame deletion affects the alpha1 helix, the alpha1-beta3 loop and the beta3 strand.