The allelic distribution of the polymorphic serum proteins AHSG, PLG, FXIIIB and HP was studied in six Jewish groups who migrated to Israel from the Middle East, North Africa, Rumania, Bulgaria, Central and Eastern Europe. The observed AHSG and PLG allele frequencies in these Jewish groups were more or less similar to the observed distributions in non-Jewish populations from their respective areas of origin, while FXIIIB and HP frequencies were similar to those in European populations. Therefore, no uniform pattern of genetic relationships between the Jewish groups was observed. A genetic distance analysis including comparative data from Europe and the Middle East reflected differences between the Jewish groups according to their areas of origin.