SAW: a graphical user interface for the analysis of immunoglobulin variable domain sequences.

The Sequence Analysis Workshop (SAW) is an interactive program for sequence analysis of immunoglobulin variable domains. Sequences for SAW can be obtained from GenBank or from a standard text file. SAW can compare a variable domain to as many as 100 different sequences, calculate the extent of homology, sort the sequences by their degree of similarity, translate the nucleotide codons into amino acids and then display the results in either a graphical or text format. These comparisons allow the investigator to determine the likely germ-line progenitors of a variable domain and to visualize how it differs from other antibody genes by functional region. SAW supports replacement and silent site substitution analysis by either codon or region, thus providing rapid insight into the forces that have shaped mutations. The sequence comparisons can be printed out as an aid for paper analysis or for preparation of figures for publication. SAW is written in Microsoft C for use with the Microsoft Windows graphics environment. The use of color and graphics, the generation of subsidiary windows that contain the results of specific analyses and the mouse-driven control of the program make SAW an easy-to-use tool for immunoglobulin sequence comparison.