MegAlign for Mac

From DNASTAR:

MegAlign offers you a choice of four pairwise and four multiple sequence alignment methods for aligning nucleic acid or polypeptide sequences. Enter your own sequences or load public data directly from NCBI*. If you want to find more related sequences for alignment, simply run a BLAST query or utilize the Entrez text query interface*, then drop in the sequences you want from the list of matches. Easily customize views of alignments to highlight the similarities or differences of the sequences. Differences in chemical, structural or functional characteristics between sequences can also be displayed as well as your own groupings or consensi. You may create a subalignment from the current alignment by simply selecting a sub-region. MegAlign also enables you to construct phylogenetic trees, generate detailed numerical reports or export data of sequence comparisons. Whether you want to compare gene families or sequence pairs, MegAlign provides you with flexible tools for customizing output for presentation and publication.