For DOS seq-analysis software try seqaid from the Indiana Molbio server. ftp ftp.bio.indiana.edu login:anonymous userid:your email address cd molbio/ibmpc binary get sqaid381.exe go to DOS type sqaid381 and let it dearchive itself and voila a pseudo not quite a Mac but does very nicely PC-DNA Strider... and it even does alignments! Nige Walker Johns Hopkins