Just use split. You are just looking 3 commas back in the list so: 

while(<DATA>) {
    my ($name, $data) = split "=";
    my @data = split ',', $data;
    for my $i ( 0.. $#data ) {
      next unless $data[$i] eq 'ResGen';
      # found a ResGen so see what we had 3 commas ago (do bounds chec
+k to0)
      next if $i -3 < 0;
      my $back_a_bit = $data[$i -3];
      print chop($back_a_bit) eq '"' ? "$name: Found quote\n" : "$name
+: No quote\n";
    }
}
   
__DATA__
GENE1="Rattus norvegicus serum and glucocorticoid-regulated kinase (sg
+k) mRNA, complete cds,NM_019232,333,ResGen,ATP binding|protein serine
+/threonine kinase|protein amino acid phosphorylation,,,,29517
GENE2="ESTs, Weakly similar to putative serine/threonine protein kinas
+e MAK-V [M.musculus]",NM_144755,331,ResGen,,,,,246273
GENE3="Thiosulfate sulphurtransferase (rhodanese)",X56228,329,ResGen,m
+itochondrion|sulfatetransport|thiosulfate sulfurtransferase,,,,25274
GENE4="Spleen tyrosine kinase,NM_012758,327,ResGen,ATP binding|protein
+ tyrosine kinase|intracellular signaling cascade|protein amino acid p
+hosphorylation,,,,25155
GENE5="Spleen kinase 24,NM_012758,,ResGen,ATP binding|protein tyrosine
+ kinase|intracellular signaling cascade|protein amino acid phosphoryl
+ation,,,,25155

__END__
GENE1: No quote
GENE2: Found quote
GENE3: Found quote
GENE4: No quote
GENE5: No quote

[download]

Update

Fixed typo thanks to Hoffmator

cheers

tachyon

s&&rsenoyhcatreve&&&s&n.+t&"$'$`$\"$\&"&ee&&y&srve&&d&&print

In reply to Re: Need method to create Regular expression for known pattern in the middle of a line by tachyon
in thread Need method to create Regular expression for known pattern in the middle of a line by Ya

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