title: The X chromosome Alu insertions as a tool for human population genetics: data from European and African human groups.
abstract: Alu elements are the most abundant mobile elements in the human genome (approximately 1,100,000 copies). Polymorphic Alu elements have been proved to be useful in studies of human origins and relationships owing to two important advantages: identity by descent and absence of the Alu element known to be the ancestral state. Alu variation in the X chromosome has been described previously in human populations but, as far as we know, these elements have not been used in population relationship studies. Here, we describe the allele frequencies of 13 'young' Alu elements of the X chromosome (Ya5DP62, Ya5DP57, Yb8DP49, Ya5a2DP1, Yb8DP2, Ya5DP3, Ya5NBC37, Yd3JX437, Ya5DP77, Ya5NBC491, Yb8NBC578, Ya5DP4 and Ya5DP13) in six human populations from sub-Saharan Africa (the Ivory Coast), North Africa (Moroccan High Atlas, Siwa oasis in Egypt, Tunisia), Greece (Crete Island) and Spain (Basque Country). Eight out of 13 Alu elements have shown remarkably high gene diversity values in all groups (average heterozygosities: 0.342 in the Ivory Coast, 0.250 in North Africa, 0.209 in Europe). Genetic relationships agree with a geographical pattern of differentiation among populations, with some peculiar features observed in North Africans. Crete Island and the Basque Country show the lowest genetic distance (0.0163) meanwhile Tunisia, in spite of its geographical location, lies far from the other two North African samples. The results of our work demonstrate that X chromosome Alu elements comprise a reliable set of genetic markers useful to describe human population relationships for fine-scale geographical studies.
authors.affiliation: Unitat d'Antropologia, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain.
authors.forename: Georgios
authors.initials: G
authors.lastname: Athanasiadis
authors.forename: Esther
authors.initials: E
authors.lastname: Esteban
authors.forename: Marc
authors.initials: M
authors.lastname: Via
authors.forename: Jean-Michel
authors.initials: JM
authors.lastname: Dugoujon
authors.forename: Nicholas
authors.initials: N
authors.lastname: Moschonas
authors.forename: Hassen
authors.initials: H
authors.lastname: Chaabani
authors.forename: Pedro
authors.initials: P
authors.lastname: Moral
mesh_terms: D000349:Africa; D020087:Alu Elements / Q000235:genetics*; D044383:Black People / Q000235:genetics*; D041321:Chromosomes, Human, X / Q000235:genetics*; D005060:Europe; D005787:Gene Frequency; D040961:Genetic Drift; D005819:Genetic Markers; D005828:Genetics, Population; D006579:Heterozygote; D006801:Humans; D010802:Phylogeny; D044465:White People / Q000235:genetics*
chemical_list: D005819:Genetic Markers