title: Y-chromosome diversity in Catalan surname samples: insights into surname origin and frequency.
abstract: The biological behavior of the Y chromosome, which is paternally inherited, implies that males sharing the same surname may also share a similar Y chromosome. However, socio-cultural factors, such as polyphyletism, non-paternity, adoption, or matrilineal surname transmission, may prevent the joint transmission of the surname and the Y chromosome. By genotyping 17 Y-STRs and 68 SNPs in ~2500 male samples that each carried one of the 50 selected Catalan surnames, we could determine sets of descendants of a common ancestor, the population of origin of the common ancestor, and the date when such a common ancestor lived. Haplotype diversity was positively correlated with surname frequency, that is, rarer surnames showed the strongest signals of coancestry. Introgression rates of Y chromosomes into a surname by non-paternity, adoption, and transmission of the maternal surname were estimated at 1.5-2.6% per generation, with some local variation. Average ages for the founders of the surnames were estimated at ~500 years, suggesting a delay between the origin of surnames (twelfth and thirteenth centuries) and the systematization of their paternal transmission. We have found that, in general, a foreign etymology for a surname does not often result in a non-indigenous origin of surname founders; however, bearers of some surnames with an Arabic etymology show an excess of North African haplotypes. Finally, we estimate that surname prediction from a Y-chromosome haplotype, which may have interesting forensic applications, has a ~60% sensitivity but a 17% false discovery rate.
authors.affiliation: Departament de Ciències Experimentals i de la Salut, Institute of Evolutionary Biology (CSIC-Universitat Pompeu Fabra), Universitat Pompeu Fabra, CEXS-UPF-PRBB, Barcelona, Catalonia, Spain.
authors.forename: Neus
authors.initials: N
authors.lastname: Solé-Morata
authors.affiliation: Departament de Ciències Experimentals i de la Salut, Institute of Evolutionary Biology (CSIC-Universitat Pompeu Fabra), Universitat Pompeu Fabra, CEXS-UPF-PRBB, Barcelona, Catalonia, Spain.
authors.forename: Jaume
authors.identifier: http://orcid.org/0000-0003-0100-0590
authors.initials: J
authors.lastname: Bertranpetit
authors.affiliation: Departament de Ciències Experimentals i de la Salut, Institute of Evolutionary Biology (CSIC-Universitat Pompeu Fabra), Universitat Pompeu Fabra, CEXS-UPF-PRBB, Barcelona, Catalonia, Spain.
authors.forename: David
authors.initials: D
authors.lastname: Comas
authors.affiliation: Departament de Ciències Experimentals i de la Salut, Institute of Evolutionary Biology (CSIC-Universitat Pompeu Fabra), Universitat Pompeu Fabra, CEXS-UPF-PRBB, Barcelona, Catalonia, Spain.
authors.forename: Francesc
authors.initials: F
authors.lastname: Calafell
mesh_terms: D041322:Chromosomes, Human, Y; D050173:Genes, Y-Linked; D005828:Genetics, Population; D005838:Genotype; D006239:Haplotypes; D006801:Humans; D008297:Male; D009275:Names; D020641:Polymorphism, Single Nucleotide; D035503:Sociobiology; D013030:Spain