The frequency of private electrophoretic variants and indirect estimates of mutation rate in scheduled tribes from South India.

Data on private electrophoretic variants for 18 Scheduled Tribe populations from south India have been utilized to estimate mutation rate by two indirect procedures. The values of mu for the total pooled data are 0.150 x 10(-6) and 0.264 x 10(-6)/locus per generation by the methods of Kimura and Ohta30 and Nei44 respectively. Three different groups of these tribes yield the unweighted average values of mu as 0.193 x 10(-6) and 0.410 x 10(-6)/locus per generation by the two methods given above. The estimates on individual populations, however, show a wide variability, even if only the non-zero results are considered. The unweighted average of these individual tribe estimates is an order of magnitude higher than the estimates obtained for the total populations of all the 18 tribes. The problems involved in estimating mutation rate from protein data using indirect methods in tribal populations of India are considerable because of their levels of detribalization and acculturation. The validity of the low values of mu in these tribes, in comparison with the much higher estimates for the populations from the other parts of the world, is discussed.