Anonymous Monk,
Parsing CSV (where C stands for character) using split or regexes can be fragile. Perhaps you don't have to worry about embedded delimiters or multi-line records, but it doesn't take much more effort to future proof your code by handling them now. (untested)

#!/usr/bin/perl
use strict;
use warnings;
use Text::CSV;

my $file = $ARGV[0] or die "Usage: $0 <input_file>";
open(my $fh, '<', $file) or die "Unable to open '$file' for reading: $
+!";

my $csv = Text::CSV->new({sep_char => "\t", binary => 1});
$csv->column_names($csv->getline($fh));
while (my $hr = $csv->getline_hr($fh)) {
    print "Amino acid is: $hr->{SEQ} and Prediction is: $hr->{PRD}\n";
}
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