Serial coalescent simulations suggest a weak genealogical relationship between Etruscans and modern Tuscans

Abstract

The Etruscans, the only preclassical European population that has been genetically characterized so far, share only two haplotypes with their modern geographic counterparts, the Tuscans, who, nonetheless, appear to be their closest relatives. We modeled 10 demographic scenarios spanning the last 2,500 years and tested by serial coalescent simulation whether any are consistent with the patterns of genetic diversity observed within and between the Etruscan and the modern Tuscan populations. Models in which the Etruscans are the direct ancestors of modern Tuscans appear compatible with the observed data only when they also include a very high mutation rate and an ancient founder effect. A better fit was obtained when the ancient and the modern samples were extracted from two independently evolving populations, connected by little migration. Simulated and observed parameters were also similar for a scenario in which the ancient samples came from a subset, e.g., a social elite, genetically differentiated from the bulk of the Etruscan population. In principle, these results may be biased by factors such as gross and systematic errors in the ancient DNA sequences and failure to sample suitable modern individuals. If neither proves to be the case, this study strongly suggests that either the mitochondrial mutation rate is much higher than currently believed or the Etruscans left very few modern mitochondrial descendants.ancient DNA ͉ mtDNA ͉ population genetics

The Etruscan timeline: a recent Anatolian connection

“…Analysis performed by coalescent simulations 21 suggested a model with little or no continuity between Ancient Etruscans and Modern Tuscans. However, the ancient dataset was extremely small and only a larger sample size would set the issue of diachronic continuity in Tuscany.…”

Coalescent simulations of Yakut mtDNA variation suggest small founding population

“…In order to evaluate the overall significance of the individual models, the method described by Belle et al (2006) was employed. The empirical likelihood (P) for each of the observed diversity measures given the parameters of the different demographic scenarios were computed relative to the diversity statistics obtained from the simulated data.…”

Mitochondrial DNA reveals distinct evolutionary histories for Jewish populations in Yemen and Ethiopia

“…The resultant N ef plot demonstrated a mode of 224 effective females, with a mean of 364 and 95% quartiles of 64 and 939. Though small, these values are similar to estimates of other founding populations, such as the Etruscans with an N ef of 770 women (Belle et al, 2006). Using this empirically-derived range of estimates for N ef , we implemented our simulation technique that was designed to provide sufficient variation in order to obtain a more precise estimate of the origin of the 16305(T) variant.…”