$hash_geno_group{$sample_geno_group}{"sample"}=$sample_nm; 

##</code><code>##

push @{ $hash_geno_group{$sample_geno_group}{sample} }, $sample_nm;

##</code><code>##

Use of my $_ is experimental at test_fontion4.pl line 68.
keys on reference is experimental at test_fontion4.pl line 187.

##</code><code>##

while (defined(my $_ = <GENOTYPED>))

##</code><code>##

while (<GENOTYPED>)

##</code><code>##

keys %{ $hash_ref }

##</code><code>##

open my $genotyped_fh, '<', $list_geno or die "Cannot open $list_geno\n";