%frequencyColors = reverse %bindersBla

are the different frequencies.

scalar keys will give you the number.

Now you are free to set the values to colors.

Please show some effort and try to hack it by yourself now.

update

To late. ...

#!/usr/bin/perl                                                       
+            
use strict;
use warnings;

use Color::Spectrum qw/generate/;
use List::MoreUtils qw/uniq/;
use Data::Dump qw/pp/;

my %peptides = (
    HISCLTFGR => 16,
    MQLFHLCLI => 8,
    WGMDIDPYK => 4,
    YVNVNMGLK => 3,
    AYRPPNAPI => 2,
    ELMNLATWV => 2,
    EYLVSFGVW => 1,
    FFPSIRDLL => 1,
    FLPSDFFPS => 1,
    IISCSCPTV => 1
    );

my @unique_indices = uniq values %peptides;
my $num_colours = scalar @unique_indices;
my @colours = generate($num_colours, '#FF0000', '#0060BF');
my %values_to_colours;
$values_to_colours{$unique_indices[$_]} = $colours[$_] for 0..$#colour
+s;


pp %values_to_colours;
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