Serum protein (haptoglobin types; transferrin and group-specific component subtypes); haemoglobin and red cell enzymes (acid phosphatase, esterase D, glyoxalase I, 6-phosphogluconate dehydrogenase, adenylate kinase, and phosphoglucomutase (locus 1) (subtypes) were studied in the Sinhalese, Tamils, and Muslims of Sri Lanka. The allelic frequencies of all the polymorphic systems were similar in these populations without any significant differences. A close look at the present results and earlier investigations on 13 polymorphic loci controlled by 37 alleles did not reveal any genetic characteristics in the present-day Sinhalese population that are distinct from those in the Tamils of Sri Lanka. As such, genetic evidence linking the legendary origin of the Sinhalese population to East India (Prince Vijaya) is lacking.