Your friend is studying the effects of a mutation in the orf of a gene. the mutation, which changes an a to a t occurs toward the center of the gene. your friend does not know the sequence at the 5' end of the mrna but scans the central region of the mrna that contains the mutation and finds it results in 5’…gggctauacuauccgcga…3’ becoming 5’…gggctauacuaaccgcga…3’ with the changed base underlined and in red. he hypothesizes that uau encoding for tyr is replaced by uaa encoding stop due to this mutation. disappointed, he finds that the mutant protein is the same size as the wt and the mutant individuals have no difference in phenotype. what mistake did he make?