"What Injures Royalty" Surnames, Inbreeding, and Genetic Structure in Sevier County, Tennessee: 1856-1905

Inbreeding in Southern Appalachia has been a topic of discourse for both local color writers and academicians since the late 19th century, but only a few researchers have aspired to measure inbreeding or describe the genetic structure of Appalachian populations. This study attempts to assess the genetic structure in one small section of Appalachia--Sevier County, Tennessee.

Because surnames, like alleles, are inherited from a parent, their distribution on a population can give clues about the genetic structure of that population--including the degree of inbreeding. Census and marriage records from 1856-1905 were examined using several methods of surname analysis, and estimates of kinship and inbreeding were calculated for the county, and for each fifteen civil districts within the county. Genetic distances were calculated between all districts, and repeated pairs analysis was applied to the marriage records.

Inbreeding and kinship coefficients in Sevier County were lower than those observed in true isolate populations, but the large nonrandom components of the inbreeding coefficients and in the repeated pairs analysis indicate subdivision of the breeding population. Kinship was notably higher in the mountain districts than in low-lying districts indicating some geographic constraint on gene flow. Cultural and economic influences on gene flow were also examined.