Abstract: | The frequencies and spectra of surnames have been analyzed in groups of raions (districts) of the Belgorod oblast (region) with different degrees of population subdivision. The "family name portraits" of districts with low (0.00003 less sign f* < 0.00022, f*(r) = 0.00015) and moderate (0.00023 < f*(r) < 0.00042, f*(r) = 0.00029) inbreeding levels are similar both to each other and to the "family name portrait" of the Belgorod oblast as a whole. Districts with high subdivision levels (0.00043 < f*(r) < 0.00125, f*(r) = 0.00072) had very distinctive surname spectra and the highest surname frequencies. Intense immigration to the Belgorod oblast significantly affects its population genetic structure, decreasing the population subdivision. |