Ten different population groups of Assam – Brahmins, Kalitas, Kaibartas, Rajbanshis, Muslims, Ahoms, Chutias, Kacharis, Karbis and Sandwals – have been typed for haptoglobin and for transferrin (Tf) and Gc subtype polymorphisms. Tf and Gc allele subtype frequencies show a considerable inter-population heterogeneity. From genetic distance analysis it appears that the populations under study form some distinct clusters, which can be explained by the historical and ethnic affiliations of these populations. Especially the distribution of Gc subtype alleles reveals some Mongoloid admixture among Assamese populations, which is reflected by the presence of Gc1A8 alleles in t