A fragment of a wild-type polypeptide is sequenced for seven amino acids. The same polypeptide region is sequenced in four mutants. Wild-type N . . . Thr-His-Ser-Gly-Leu-Lys-Ala . . . C polypeptide
Mutant 1 N . . . Thr-His-Ser-Val-Leu-Lys-Ala . . . C
Mutant 2 N. . . Thr-His-Ser-C
Mutant 3 N . . . Thr-Thr-Leu-Asp-C
Mutant 4 N . . . Thr-Gln-Leu-Trp-Ile-Glu-Gly . . . C

Required:
Determine the wild-type mRNA sequence.