I'm not sure it's easy to do it in just one regex.

But you can just use two steps:

my $seq = "G_I1E2_GTGGAG^303CTGgacgCCCTGC_I2E3_TACA";
$seq =~ s/[^ACTGactg]//g;
my @result = $seq =~ /[ACTG]+/g;
say for @result;

[download]

You can do it in one line if your version of perl is recent enough to support the r regex modifier:

perl -wE 'say for "G_I1E2_GTGGAG^303CTGgacgCCCTGC_I2E3_TACA" =~ s/[^AC
+TGactg]//gr =~ /[ACTG]+/g;'

[download]

In reply to Re: extract only uppercases from string by grondilu
in thread extract only uppercases from string by losher

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