http://sci-hub.tw/https://www.nature.com/articles/s41431-019-0361-1
People from Ibiza: an unexpected isolate in the WesternMediterranean
Simone Andrea Biagini1●Neus Solé-Morata1●Elizabeth Matisoo-Smith2●Pierre Zalloua3●David Comas1●Francesc Calafell1Received: 10 August 2018 / Revised: 15 January 2019 / Accepted: 24 January 2019© European Society of Human Genetics 2019
Abstract
In this study, we seek to understand and to correlate the genetic patterns observed in the population of the island of Ibiza in the Western Mediterranean basin with past events. Genome-wide genotypes of 189 samples representing 13 of 17 regions inSpain have been analyzed, in addition to 105 samples from the Levant, 157 samples from North Africa, and one ancient sample from the Phoenician Cas Molí site in Ibiza. Before the Catalans conquered the island in 1235 CE, Ibiza (Eivissa) had already been influenced by several cultures, starting with the Phoenicians, then the Carthaginians, followed by the Umayyads. The impact of these various cultures on the genetic structure of the islanders is still unexplored. Our results show a clear distinction between Ibiza and the rest of Spain. To investigate whether this was due to the Phoenician colonization or to more recent events, we compared the genomes of current Ibizans to that of an ancient Phoenician sample from Ibiza and to both modern Levantine and North African genomes. We did not identify any trace of Phoenician ancestry in the current Ibizans. Interestingly, the analysis of runs of homozygosity and changes in the effective population size through time support the idea that drift has shaped the genetic structure of current Ibizans. In addition to the small carrying capacity of the island,Ibiza experienced a series of dramatic demographic changes due to several instances of famine, war, malaria and plague that could have significantly contributed to its current genetic differentiation.
A sample (MS10614) from the Phoenician Cas Molí site inIbiza [13] was sequenced at a 0.47X coverage, and wasprojected into a PCA space with two modern groups ofsamples, from Iberia (including contemporary Ibiza) and theLevant (Supplementary Figure S7a). The ancient Phoeni-cian sample clusters with the modern Levantines, ratherthan with the cluster represented by the core regions. Fur-thermore, the admixture proportions seem to be consistentwith this result (Supplementary Figure S7b). In thefigure,the average percentage for each component is displayed foreach group; it is clear that the ancient sample is closelyrelated to the groups from Levant. And, conversely, theseresults seem to be incompatible with direct continuitybetween the current population of Ibiza and the ancientPhoenicians who settled the island.
People from Ibiza: an unexpected isolate in the WesternMediterranean
Simone Andrea Biagini1●Neus Solé-Morata1●Elizabeth Matisoo-Smith2●Pierre Zalloua3●David Comas1●Francesc Calafell1Received: 10 August 2018 / Revised: 15 January 2019 / Accepted: 24 January 2019© European Society of Human Genetics 2019
Abstract
In this study, we seek to understand and to correlate the genetic patterns observed in the population of the island of Ibiza in the Western Mediterranean basin with past events. Genome-wide genotypes of 189 samples representing 13 of 17 regions inSpain have been analyzed, in addition to 105 samples from the Levant, 157 samples from North Africa, and one ancient sample from the Phoenician Cas Molí site in Ibiza. Before the Catalans conquered the island in 1235 CE, Ibiza (Eivissa) had already been influenced by several cultures, starting with the Phoenicians, then the Carthaginians, followed by the Umayyads. The impact of these various cultures on the genetic structure of the islanders is still unexplored. Our results show a clear distinction between Ibiza and the rest of Spain. To investigate whether this was due to the Phoenician colonization or to more recent events, we compared the genomes of current Ibizans to that of an ancient Phoenician sample from Ibiza and to both modern Levantine and North African genomes. We did not identify any trace of Phoenician ancestry in the current Ibizans. Interestingly, the analysis of runs of homozygosity and changes in the effective population size through time support the idea that drift has shaped the genetic structure of current Ibizans. In addition to the small carrying capacity of the island,Ibiza experienced a series of dramatic demographic changes due to several instances of famine, war, malaria and plague that could have significantly contributed to its current genetic differentiation.
A sample (MS10614) from the Phoenician Cas Molí site inIbiza [13] was sequenced at a 0.47X coverage, and wasprojected into a PCA space with two modern groups ofsamples, from Iberia (including contemporary Ibiza) and theLevant (Supplementary Figure S7a). The ancient Phoeni-cian sample clusters with the modern Levantines, ratherthan with the cluster represented by the core regions. Fur-thermore, the admixture proportions seem to be consistentwith this result (Supplementary Figure S7b). In thefigure,the average percentage for each component is displayed foreach group; it is clear that the ancient sample is closelyrelated to the groups from Levant. And, conversely, theseresults seem to be incompatible with direct continuitybetween the current population of Ibiza and the ancientPhoenicians who settled the island.