The application of isoelectric focusing (IEF) in molluscan systematics
is reviewed and illustrated using literature data and unpublished ana
lyses. IEF can be used as any other electrophoretic method, but is mos
t appropriate for: (1) generating complex species-specific banding pro
files, (2) assessing overall genetic similarities, (3) supplementing c
onventional electrophoretic techniques by resolving hidden protein var
iation and (4) investigating minute organisms.