Bell and Sstl restriction fragment length polymorphisms of human liver/bone/kidney or tissue-non-specific alkaline phosphatase were studied in population samples of Finns, Swedes and Swedish Saamis. No significant allele frequency differences were found between the three ethnic groups, but in comparison with a previously reported study of North American Caucasians, a highly significant difference was found with respect to BclI alleles. In contrast to previous findings, a significant linkage disequilibrium was found betweeen BclI and Sstl alleles.