title: An overview of the genetic structure within the Italian population from genome-wide data.
abstract: In spite of the common belief of Europe as reasonably homogeneous at genetic level, advances in high-throughput genotyping technology have resolved several gradients which define different geographical areas with good precision. When Northern and Southern European groups were considered separately, there were clear genetic distinctions. Intra-country genetic differences were also evident, especially in Finland and, to a lesser extent, within other European populations. Here, we present the first analysis using the 125,799 genome-wide Single Nucleotide Polymorphisms (SNPs) data of 1,014 Italians with wide geographical coverage. We showed by using Principal Component analysis and model-based individual ancestry analysis, that the current population of Sardinia can be clearly differentiated genetically from mainland Italy and Sicily, and that a certain degree of genetic differentiation is detectable within the current Italian peninsula population. Pair-wise F(ST) statistics Northern and Southern Italy amounts approximately to 0.001 between, and around 0.002 between Northern Italy and Utah residents with Northern and Western European ancestry (CEU). The Italian population also revealed a fine genetic substructure underscoring by the genomic inflation (Sardinia vs. Northern Italy = 3.040 and Northern Italy vs. CEU = 1.427), warning against confounding effects of hidden relatedness and population substructure in association studies.
authors.affiliation: Department of Genetics, Biology and Biochemistry, University of Turin, Turin, Italy. cornelia.digaetano@unito.it
authors.forename: Cornelia
authors.initials: C
authors.lastname: Di Gaetano
authors.forename: Floriana
authors.initials: F
authors.lastname: Voglino
authors.forename: Simonetta
authors.initials: S
authors.lastname: Guarrera
authors.forename: Giovanni
authors.initials: G
authors.lastname: Fiorito
authors.forename: Fabio
authors.initials: F
authors.lastname: Rosa
authors.forename: Anna Maria
authors.initials: AM
authors.lastname: Di Blasio
authors.forename: Paola
authors.initials: P
authors.lastname: Manzini
authors.forename: Irma
authors.initials: I
authors.lastname: Dianzani
authors.forename: Marta
authors.initials: M
authors.lastname: Betti
authors.forename: Daniele
authors.initials: D
authors.lastname: Cusi
authors.forename: Francesca
authors.initials: F
authors.lastname: Frau
authors.forename: Cristina
authors.initials: C
authors.lastname: Barlassina
authors.forename: Dario
authors.initials: D
authors.lastname: Mirabelli
authors.forename: Corrado
authors.initials: C
authors.lastname: Magnani
authors.forename: Nicola
authors.initials: N
authors.lastname: Glorioso
authors.forename: Stefano
authors.initials: S
authors.lastname: Bonassi
authors.forename: Alberto
authors.initials: A
authors.lastname: Piazza
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Matullo
mesh_terms: D044383:Black People; D016000:Cluster Analysis; D030541:Databases, Genetic; D005789:Genealogy and Heraldry; D005828:Genetics, Population; D015894:Genome, Human / Q000235:genetics*; D055106:Genome-Wide Association Study; D006801:Humans; D007558:Italy; D008877:Middle East; D008957:Models, Genetic; D020641:Polymorphism, Single Nucleotide; D025341:Principal Component Analysis; D012984:Software; D044465:White People / Q000235:genetics