A Genetic study of the Veddas of Sri Lanka

ABSTRACT

The study of primitive tribes like the Veddas has an urgency for the following reason. They have lived under conditions which approximate closely to the greater part of man's existence, but today they face a threat of extinction as a community owing to the rapid absorption of the culture of the Sinhalese which will be more accentuated as they begin living together with the Sinhalese in the new settlements of the Mahaweli.The anthropoiemetric studies of earlier workers indicate that the present day Vedda has a mixed ancestry of Sinhalese Australoid, Negroid stock together with features which belonged to the Prehistoric man of Sri Lanka, who was referred toa as Homo sapiens balangodensis. (Balangoda man) The recent development in the detection of single gene multi allele systems by starch gel electrophoresis has made it possible to study many new genetic markers like serum proteins and red cell enzymes. In the present study a total of twenty six alleles both multi and single allele systems were studied. A comparison of the allele systems of the Veddas and Sinhalese show a genetic identity between them of 0.9905 with a genetic distance of 0.0095 and a phylogenetic time of 47,500 years. Therefore there is a possibility that the Veddas may have a link with the Homosapients Balangodensis ("Balangoda Man") and his ancestors who belonged to the Paleolitic and Mesolithic periods of Sri Lanka in addition to the link with the Sinhalese. A comparison of the allele frequencies of the Vedda with the primitive tribes of Asia and Oceania demonstrate that they are closely related to the primitive tribes of Malaysia or the Negrito of the Philippine Islands. All these tribes however appears to be of Asiatic origin. One of the interesting features seen in the Veddas when compared with Sinhalese was the higher frequency of Haemoglobin E and of Glucose six phosphate dehydrogenase deficiency in them. This may be due to natural selection which may have afforded them protection against malaria. There is a also a higher incidence of Hepatitis B antigen and antibodies in the Veddas when compared with the Sinhalese which may also be due to genetic factors. The other diseases like yaws and asthma found in the Vedda is due to local conditions and the life style of the Vedda.