[The genes of the Pascuense population]

An analysis of the interaction of evolutionary factors such as migration, mutation, selection random drift, and consanguinity upon the genome of Easter islanders is attempted. As many primitive populations, the Easter islanders genome has at least 2/3 of genetic loci in an isogenic state. The HLA system is reduced; other polymorphisms present high genic frequencies differentiating Easter islanders from other Andean and european populations. They are more similar to polynesians, with whom they share language and culture. Migration has been the main factor affecting the Easter islanders genome, leading to a ten fold increase in population and a 60% caucasian admixture. A linkage disequilibrium of the HLA9, w10 haplotype exists. In XIX century generations consanguinity was very low (alpha coefficient 7 x 10(-5) which may be explained by the exogamic tradition of the population; this acted as a factor opposed to random drift. A recent decrease in infant mortality rate leads to a relaxation of natural selection and contributes to hybridization of the population.