I have another question to add to the original question. Can anyone lead me to a good review article explaining the retrotransposons? I may have one linked to a gene that I am looking for. Thanks! Paul "Goose" Ulanch Dept. Biochem/Biophys Texas A&M University College Station, TX 77843-2128 (409) 847-9379 PULANCH at bioch.tamu.edu