Sostituzione print removing white space\n ; $dna = ATG CATTT CGCATAG ; print Old DNA: $dna\n ; $dna =~ s/\s//g; print New DNA: $dna\n\n ; removing white space Old DNA: ATG CATTT CGCATAG New DNA: ATGCATTTCGCATAG print substitution ignoring case\n ; $dna = ATGCAttT ; print Old DNA: $dna\n ; $dna =~ s/T/U/gi; print New DNA: $dna\n\n ; substitution ignoring case Old DNA: ATGCAttT New DNA: AUGCAUUU