Will this do what you want?

use strict;

my @genes;
my $screen = "ATCGATCGXXXXXATCGATXXXACTGCTACGGTACXXXAATTATXGCGCGXXT";

while ($screen =~ /(^|(?<=X))([^X]+)/g) {
    print "Gene $2 found at position ", length($`), "\n";
}

[download]

Update: added $2 gene string.

In reply to Re: Split Function - Positions by meetraz
in thread Split Function - Positions by MiamiGenome

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