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1.
Int J Mol Sci ; 23(12)2022 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-35743173

RESUMEN

The high number of matching haplotypes of the most common mitochondrial (mt)DNA lineages are considered to be the greatest limitation for forensic applications. This study investigates the potential to solve this constraint by massively parallel sequencing a large number of mitogenomes that share the most common West Eurasian mtDNA control region (CR) haplotype motif (263G 315.1C 16519C). We augmented a pilot study on 29 to a total of 216 Italian mitogenomes that represents the largest set of the most common CR haplotype compiled from a single country. The extended population sample confirmed and extended the huge coding region diversity behind the most common CR motif. Complete mitogenome sequencing allowed for the detection of 163 distinct haplotypes, raising the power of discrimination from 0 (CR) to 99.6% (mitogenome). The mtDNAs were clustered into 61 named clades of haplogroup H and did not reveal phylogeographic trends within Italy. Rapid individualization approaches for investigative purposes are limited to the most frequent H clades of the dataset, viz. H1, H3, and H7.


Asunto(s)
ADN Mitocondrial , Genoma Mitocondrial , ADN Mitocondrial/genética , Genética de Población , Haplotipos/genética , Núcleo Familiar , Proyectos Piloto , Análisis de Secuencia de ADN
2.
Am J Phys Anthropol ; 175(3): 665-679, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33969895

RESUMEN

OBJECTIVES: Genetic drift and admixture are driving forces in human evolution, but their concerted impact to population evolution in historical times and at a micro-geographic scale is poorly assessed. In this study we test a demographic model encompassing both admixture and drift to the case of social-cultural isolates such as the so-called "Commons." MATERIALS AND METHODS: Commons are peculiar institutions of medieval origins whose key feature is the tight relationship between population and territory, mediated by the collective property of shared resources. Here, we analyze the Y-chromosomal genetic structure of four Commons (for a total of 366 samples) from the Central and Eastern Padana plain in Northern Italy. RESULTS: Our results reveal that all these groups exhibit patterns of significant diversity reduction, peripheral/outlier position within the Italian/European genetic space and high frequency of Common-specific haplogroups. By explicitly testing different drift-admixture models, we show that a drift-only model is more probable for Central Padana Commons, while additional admixture (~20%) from external population around the same time of their foundation cannot be excluded for the Eastern ones. DISCUSSION: Building on these results, we suggest central Middle Ages as the most probable age of foundation for three of the considered Commons, the remaining one pointing to late antiquity. We conclude that an admixture-drift model is particularly useful for interpreting the genetic structure and recent demographic history of small-scale populations in which social-cultural features play a significant role.


Asunto(s)
Cromosomas Humanos Y , Flujo Genético , Cromosomas Humanos Y/genética , Variación Genética/genética , Genética de Población , Haplotipos , Humanos , Italia
3.
BMC Biol ; 18(1): 51, 2020 05 22.
Artículo en Inglés | MEDLINE | ID: mdl-32438927

RESUMEN

BACKGROUND: The cline of human genetic diversity observable across Europe is recapitulated at a micro-geographic scale by variation within the Italian population. Besides resulting from extensive gene flow, this might be ascribable also to local adaptations to diverse ecological contexts evolved by people who anciently spread along the Italian Peninsula. Dissecting the evolutionary history of the ancestors of present-day Italians may thus improve the understanding of demographic and biological processes that contributed to shape the gene pool of European populations. However, previous SNP array-based studies failed to investigate the full spectrum of Italian variation, generally neglecting low-frequency genetic variants and examining a limited set of small effect size alleles, which may represent important determinants of population structure and complex adaptive traits. To overcome these issues, we analyzed 38 high-coverage whole-genome sequences representative of population clusters at the opposite ends of the cline of Italian variation, along with a large panel of modern and ancient Euro-Mediterranean genomes. RESULTS: We provided evidence for the early divergence of Italian groups dating back to the Late Glacial and for Neolithic and distinct Bronze Age migrations having further differentiated their gene pools. We inferred adaptive evolution at insulin-related loci in people from Italian regions with a temperate climate, while possible adaptations to pathogens and ultraviolet radiation were observed in Mediterranean Italians. Some of these adaptive events may also have secondarily modulated population disease or longevity predisposition. CONCLUSIONS: We disentangled the contribution of multiple migratory and adaptive events in shaping the heterogeneous Italian genomic background, which exemplify population dynamics and gene-environment interactions that played significant roles also in the formation of the Continental and Southern European genomic landscapes.


Asunto(s)
Evolución Molecular , Variación Genética , Genoma Humano , Arqueología , ADN Antiguo/análisis , Humanos , Italia , Población Blanca
4.
Ann Hum Biol ; 48(3): 260-269, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-34459343

RESUMEN

BACKGROUND: Thanks to the availability of rich surname, linguistic and genetic information, together with its geographic and cultural complexity, Trentino (North-Eastern Italy) is an ideal place to test the relationships between genetic and cultural traits. AIM: We provide a comprehensive study of population structures based on surname and dialect variability and evaluate their relationships with genetic diversity in Trentino. SUBJECTS AND METHODS: Surname data were collected for 363 parishes, linguistic data for 57 dialects and genetic data for different sets of molecular markers (Y-chromosome, mtDNA, autosomal) in 10 populations. Analyses relied on different multivariate methods and correlation tests. RESULTS: Besides the expected isolation-by-distance-like patterns (with few local exceptions, likely related to sociocultural instances), we detected a significant and geography-independent association between dialects and surnames. As for molecular markers, only Y-chromosomal STRs seem to be associated with the dialects, although no significant result was obtained. No evidence for correlation between molecular markers and surnames was observed. CONCLUSION: Surnames act as cultural markers as do other words, although in this context they cannot be used as reliable proxies for genetic variability at a local scale.


Asunto(s)
ADN/análisis , Variación Genética , Lenguaje , Nombres , Cultura , Humanos , Italia
5.
Mol Biol Evol ; 36(6): 1254-1269, 2019 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-30895292

RESUMEN

Extensive European and African admixture coupled with loss of Amerindian lineages makes the reconstruction of pre-Columbian history of Native Americans based on present-day genomes extremely challenging. Still open questions remain about the dispersals that occurred throughout the continent after the initial peopling from the Beringia, especially concerning the number and dynamics of diffusions into South America. Indeed, if environmental and historical factors contributed to shape distinct gene pools in the Andes and Amazonia, the origins of this East-West genetic structure and the extension of further interactions between populations residing along this divide are still not well understood. To this end, we generated new high-resolution genome-wide data for 229 individuals representative of one Central and ten South Amerindian ethnic groups from Mexico, Peru, Bolivia, and Argentina. Low levels of European and African admixture in the sampled individuals allowed the application of fine-scale haplotype-based methods and demographic modeling approaches. These analyses revealed highly specific Native American genetic ancestries and great intragroup homogeneity, along with limited traces of gene flow mainly from the Andes into Peruvian Amazonians. Substantial amount of genetic drift differentially experienced by the considered populations underlined distinct patterns of recent inbreeding or prolonged isolation. Overall, our results support the hypothesis that all non-Andean South Americans are compatible with descending from a common lineage, while we found low support for common Mesoamerican ancestors of both Andeans and other South American groups. These findings suggest extensive back-migrations into Central America from non-Andean sources or conceal distinct peopling events into the Southern Continent.


Asunto(s)
Genoma Humano , Migración Humana , Indígenas Sudamericanos/genética , Flujo Génico , Variación Genética , Haplotipos , Humanos , Modelos Genéticos , Filogeografía , Polimorfismo de Nucleótido Simple , Análisis de Componente Principal , América del Sur
6.
Proc Natl Acad Sci U S A ; 114(34): 9140-9145, 2017 08 22.
Artículo en Inglés | MEDLINE | ID: mdl-28784786

RESUMEN

Observable patterns of cultural variation are consistently intertwined with demic movements, cultural diffusion, and adaptation to different ecological contexts [Cavalli-Sforza and Feldman (1981) Cultural Transmission and Evolution: A Quantitative Approach; Boyd and Richerson (1985) Culture and the Evolutionary Process]. The quantitative study of gene-culture coevolution has focused in particular on the mechanisms responsible for change in frequency and attributes of cultural traits, the spread of cultural information through demic and cultural diffusion, and detecting relationships between genetic and cultural lineages. Here, we make use of worldwide whole-genome sequences [Pagani et al. (2016) Nature 538:238-242] to assess the impact of processes involving population movement and replacement on cultural diversity, focusing on the variability observed in folktale traditions (n = 596) [Uther (2004) The Types of International Folktales: A Classification and Bibliography. Based on the System of Antti Aarne and Stith Thompson] in Eurasia. We find that a model of cultural diffusion predicted by isolation-by-distance alone is not sufficient to explain the observed patterns, especially at small spatial scales (up to [Formula: see text]4,000 km). We also provide an empirical approach to infer presence and impact of ethnolinguistic barriers preventing the unbiased transmission of both genetic and cultural information. After correcting for the effect of ethnolinguistic boundaries, we show that, of the alternative models that we propose, the one entailing cultural diffusion biased by linguistic differences is the most plausible. Additionally, we identify 15 tales that are more likely to be predominantly transmitted through population movement and replacement and locate putative focal areas for a set of tales that are spread worldwide.


Asunto(s)
Evolución Cultural , Folclore , Genética de Población/métodos , Genómica/métodos , África , Asia , Evolución Biológica , Europa (Continente) , Geografía , Humanos , Lingüística , Modelos Teóricos
7.
Am J Phys Anthropol ; 168(4): 717-728, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30693949

RESUMEN

OBJECTIVES: The Yaghnobis are an ethno-linguistic minority historically settled along the Yaghnob River in the Upper-Zarafshan Valley in Tajikistan. They speak a language of Old Sogdian origin, which is the only present-day witness of the Lingua Franca used along the Silk Road in Late Antiquity. The aim of this study was to reconstruct the genetic history of this community in order to shed light on its isolation and genetic ancestry within the Euro-Asiatic context. MATERIALS AND METHODS: A total of 100 DNA samples were collected in the Yaghnob and Matcha Valleys during several expeditions and their mitochondrial, Y-chromosome and autosomal genome-wide variation were compared with that from a large set of modern and ancient Euro-Asiatic samples. RESULTS: Findings from uniparental markers highlighted the long-term isolation of the Yaghnobis. Mitochondrial DNA ancestry traced an ancient link with Middle Eastern populations, whereas Y-chromosome legacy showed more tight relationships with Central Asians. Admixture, outgroup-f3, and D-statistics computed on autosomal variation corroborated Y-chromosome evidence, pointing respectively to low Anatolian Neolithic and high Steppe ancestry proportions in Yaghnobis, and to their closer affinity with Tajiks than to Iranians. DISCUSSION: Although the Yaghnobis do not show evident signs of recent admixture, they could be considered a modern proxy for the source of gene flow for many Central Asian and Middle Eastern groups. Accordingly, they seem to retain a peculiar genomic ancestry probably ascribable to an ancient gene pool originally wide spread across a vast area and subsequently reshuffled by distinct demographic events occurred in Middle East and Central Asia.


Asunto(s)
Pueblo Asiatico/genética , Etnicidad/genética , Población Blanca/genética , Antropología Física , Cromosomas Humanos Y/genética , ADN Mitocondrial/genética , Migración Humana , Humanos , Masculino , Metagenómica , Polimorfismo de Nucleótido Simple/genética , Tayikistán
8.
Ann Hum Biol ; 45(1): 57-65, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29183201

RESUMEN

BACKGROUND: Southern Italy and Sicily played a key role in the peopling history of the Mediterranean. While genetic research showed the remarkable homogeneity of these regions, surname-based studies instead suggested low population mobility, hence potential structuring. AIM: In order to better understand these different patterns, this study (1) thoroughly analysed the surname structure of Sicily and Southern Italy and (2) tested its relationships with a wide set of molecular markers. SUBJECTS AND METHODS: Surname data were collected from 1213 municipalities and compared to uniparental and autosomal genetic markers typed in ∼300 individuals from 8-10 populations. Surname analyses were performed using different multivariate methods, while comparisons with genetic data relied on correlation tests. RESULTS: Surnames were clearly structured according to regional geographic patterns, which likely emerged because of recent isolation-by-distance-like population dynamics. In general, genetic markers, hinting at a pervasive homogeneity, did not correlate with surname distribution. However, long autosomal haplotypes (>5 cM) that compared to genotypic (SNPs) data identify more "recent" relatedness, showing a clear association with surname patterns. CONCLUSION: The apparent contradiction between surname structure and genetic homogeneity was resolved by figuring surnames as recent "ripples" deposited on a vast and ancient homogeneous genetic "surface".


Asunto(s)
Variación Genética , Haplotipos , Dinámica Poblacional , Marcadores Genéticos , Humanos , Italia , Nombres , Sicilia
9.
J Biosoc Sci ; 49(1): 69-82, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-26883942

RESUMEN

In some situations the use of isonymy is the best strategy for studying the genetic structure of a population and its biological history. In this study different population parameters were calculated for one of the most isolated valleys in the Pyrenees - the region of the Alta Ribagorça in Catalonia, Spain. Surnames from marriage records covering the continuous period from 1638 to 1988 were used. From 1950 onwards this region underwent important social, economic and biological changes related to the introduction of hydroelectric and mining industries, and the change from livestock farming to a society based on services. Two periods were analysed (1638-1950 and 1951-1988) allowing population changes that occurred in the region to be determined. The study focused on calculating the number of surnames by gender, diversity index (H), population sub-structure (RP-RPr)/RPr and inbreeding coefficient (F t) and detection of possible genetic barriers. The results demonstrate the importance that geography initially had in shaping the genetic structure of the population and how this was gradually replaced by other parameters such as roads or the social and economic importance of towns. An interesting phenomenon is that inbreeding has traditionally been associated with rural life, isolation and endogamy. However, for the Alta Ribagorça it was observed that in the second period, 1951-1988, inbreeding mainly depended on the composition of migrant groups and the reaction of the native population to the arrival of migrants from outside the region.


Asunto(s)
Consanguinidad , Genética de Población , Nombres , Población Rural , Demografía , Ambiente , Femenino , Geografía , Historia del Siglo XVII , Historia del Siglo XVIII , Historia del Siglo XIX , Historia del Siglo XX , Humanos , Masculino , Matrimonio/historia , Población Rural/historia , Población Rural/estadística & datos numéricos , España
10.
Am J Hum Genet ; 93(5): 852-64, 2013 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-24568772

RESUMEN

Most ancient specimens contain very low levels of endogenous DNA, precluding the shotgun sequencing of many interesting samples because of cost. Ancient DNA (aDNA) libraries often contain <1% endogenous DNA, with the majority of sequencing capacity taken up by environmental DNA. Here we present a capture-based method for enriching the endogenous component of aDNA sequencing libraries. By using biotinylated RNA baits transcribed from genomic DNA libraries, we are able to capture DNA fragments from across the human genome. We demonstrate this method on libraries created from four Iron Age and Bronze Age human teeth from Bulgaria, as well as bone samples from seven Peruvian mummies and a Bronze Age hair sample from Denmark. Prior to capture, shotgun sequencing of these libraries yielded an average of 1.2% of reads mapping to the human genome (including duplicates). After capture, this fraction increased substantially, with up to 59% of reads mapped to human and enrichment ranging from 6- to 159-fold. Furthermore, we maintained coverage of the majority of regions sequenced in the precapture library. Intersection with the 1000 Genomes Project reference panel yielded an average of 50,723 SNPs (range 3,062-147,243) for the postcapture libraries sequenced with 1 million reads, compared with 13,280 SNPs (range 217-73,266) for the precapture libraries, increasing resolution in population genetic analyses. Our whole-genome capture approach makes it less costly to sequence aDNA from specimens containing very low levels of endogenous DNA, enabling the analysis of larger numbers of samples.


Asunto(s)
ADN/aislamiento & purificación , Fósiles , Genómica , Momias , Análisis de Secuencia de ADN/métodos , Adolescente , Huesos , Niño , ADN/química , ADN/genética , Biblioteca de Genes , Cabello , Secuenciación de Nucleótidos de Alto Rendimiento , Historia Antigua , Humanos , Masculino , Hibridación de Ácido Nucleico , Análisis de Componente Principal , ARN/genética , Diente
12.
Hum Biol ; 86(4): 251-9, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25959692

RESUMEN

Interest in mitochondrial influences on extended longevity has been mounting, as evidenced by a growing literature. Such work has demonstrated that some haplogroups are associated with increased longevity and that such associations are population specific. Most previous work, however, suffers from the methodological shortcoming that long-lived individuals are compared with "controls" who are born decades after the aged individuals. The only true controls of the elderly are people who were born in the same time period but who did not have extended longevity. Here we present results of a study in which we are able to test whether longevity is independent of haplogroup type, controlling for time period, by using mtDNA genealogies. Since mtDNA does not recombine, we know the mtDNA haplogroup of the maternal ancestors of our living participants. Thus, we can compare the haplogroup of people with and without extended longevity who were born during the same time period. Our sample is an admixed New World population that has haplogroups of Amerindian, European, and African origin. We show that women who belong to Amerindian, European, and African haplogroups do not differ in their mean longevity. Therefore, to the extent that ethnicity was tied in this population to mtDNA make-up, such ethnicity did not impact longevity. In support of previous suggestions that the link between mtDNA haplogroups and longevity is specific to the population being studied, we found an association between haplogroup C and decreased longevity. Interestingly, the lifetime reproductive success and the number of grandchildren produced via a daughter of women with haplogroup C are not reduced. Our diachronic approach to the mtDNA and longevity link allowed us to determine that the same haplogroup is associated with decreased longevity during different time periods and allowed us to compare the haplogroup of short- and long-lived individuals born during the same time period. By controlling for time period, we minimized the effect of different cultural and ecological environments on differential longevity. With our diachronic approach, we investigated the mtDNA and longevity link with a biocultural perspective.


Asunto(s)
Indio Americano o Nativo de Alaska , Población Negra , ADN Mitocondrial/genética , Haplotipos , Longevidad/genética , Población Blanca , Envejecimiento/genética , Indio Americano o Nativo de Alaska/genética , Indio Americano o Nativo de Alaska/estadística & datos numéricos , Población Negra/genética , Población Negra/estadística & datos numéricos , Costa Rica/epidemiología , Evolución Cultural , Femenino , Humanos , Masculino , Filogenia , Población Blanca/genética , Población Blanca/estadística & datos numéricos
13.
Am J Phys Anthropol ; 155(4): 600-9, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25229359

RESUMEN

The Yanesha are a Peruvian population who inhabit an environment transitional between the Andes and Amazonia. They present cultural traits characteristic of both regions, including in the language they speak: Yanesha belongs to the Arawak language family (which very likely originated in the Amazon/Orinoco lowlands), but has been strongly influenced by Quechua, the most widespread language family of the Andes. Given their location and cultural make-up, the Yanesha make for an ideal case study for investigating language and population dynamics across the Andes-Amazonia divide. In this study, we analyze data from high and mid-altitude Yanesha villages, both Y chromosome (17 STRs and 16 SNPs diagnostic for assigning haplogroups) and mtDNA data (control region sequences and 3 SNPs and one INDEL diagnostic for assigning haplogroups). We uncover sex-biased genetic trends that probably arose in different stages: first, a male-biased gene flow from Andean regions, genetically consistent with highland Quechua-speakers and probably dating back to Inca expansion; and second, traces of European contact consistent with Y chromosome lineages from Italy and Tyrol, in line with historically documented migrations. Most research in the history, archaeology and linguistics of South America has long been characterized by perceptions of a sharp divide between the Andes and Amazonia; our results serve as a clear case-study confirming demographic flows across that 'divide'.


Asunto(s)
Cromosomas Humanos Y/genética , ADN Mitocondrial/genética , Etnicidad/genética , Indígenas Sudamericanos/genética , Etnicidad/etnología , Genotipo , Haplotipos , Humanos , Indígenas Sudamericanos/etnología , Lenguaje , Masculino , Repeticiones de Microsatélite/genética , Polimorfismo de Nucleótido Simple/genética , América del Sur
14.
Am J Phys Anthropol ; 150(3): 375-85, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23283748

RESUMEN

East Africa (EA) has witnessed pivotal steps in the history of human evolution. Due to its high environmental and cultural variability, and to the long-term human presence there, the genetic structure of modern EA populations is one of the most complicated puzzles in human diversity worldwide. Similarly, the widespread Afro-Asiatic (AA) linguistic phylum reaches its highest levels of internal differentiation in EA. To disentangle this complex ethno-linguistic pattern, we studied mtDNA variability in 1,671 individuals (452 of which were newly typed) from 30 EA populations and compared our data with those from 40 populations (2970 individuals) from Central and Northern Africa and the Levant, affiliated to the AA phylum. The genetic structure of the studied populations--explored using spatial Principal Component Analysis and Model-based clustering--turned out to be composed of four clusters, each with different geographic distribution and/or linguistic affiliation, and signaling different population events in the history of the region. One cluster is widespread in Ethiopia, where it is associated with different AA-speaking populations, and shows shared ancestry with Semitic-speaking groups from Yemen and Egypt and AA-Chadic-speaking groups from Central Africa. Two clusters included populations from Southern Ethiopia, Kenya and Tanzania. Despite high and recent gene-flow (Bantu, Nilo-Saharan pastoralists), one of them is associated with a more ancient AA-Cushitic stratum. Most North-African and Levantine populations (AA-Berber, AA-Semitic) were grouped in a fourth and more differentiated cluster. We therefore conclude that EA genetic variability, although heavily influenced by migration processes, conserves traces of more ancient strata.


Asunto(s)
Población Negra/genética , ADN Mitocondrial/genética , África Oriental , Análisis de Varianza , Antropología Física , Análisis por Conglomerados , Evolución Molecular , Variación Genética , Haplotipos , Humanos , Lenguaje , Filogenia , Análisis de Componente Principal
15.
Evol Med Public Health ; 11(1): 397-414, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37954982

RESUMEN

Background and objectives: Epigenetic estimators based on DNA methylation levels have emerged as promising biomarkers of human aging. These estimators exhibit natural variations across human groups, but data about indigenous populations remain underrepresented in research. This study aims to investigate differences in epigenetic estimators between two distinct human populations, both residing in the Gran Chaco region of Argentina, the Native-American Wichí, and admixed Criollos who are descendants of intermarriages between Native Americans and the first European colonizers, using a population genetic approach. Methodology: We analyzed 24 Wichí (mean age: 39.2 ± 12.9 yo) and 24 Criollos (mean age: 41.1 ± 14.0 yo) for DNA methylation levels using the Infinium MethylationEPIC (Illumina) to calculate 16 epigenetic estimators. Additionally, we examined genome-wide genetic variation using the HumanOmniExpress BeadChip (Illumina) to gain insights into the genetic history of these populations. Results: Our results indicate that Native-American Wichí are epigenetically older compared to Criollos according to five epigenetic estimators. Analyses within the Criollos population reveal that global ancestry does not influence the differences observed, while local (chromosomal) ancestry shows positive associations between specific SNPs located in genomic regions over-represented by Native-American ancestry and measures of epigenetic age acceleration (AgeAccelHannum). Furthermore, we demonstrate that differences in population ecologies also contribute to observed epigenetic differences. Conclusions and implications: Overall, our study suggests that while the genomic history may partially account for the observed epigenetic differences, non-genetic factors, such as lifestyle and ecological factors, play a substantial role in the variability of epigenetic estimators, thereby contributing to variations in human epigenetic aging.

16.
Hum Biol ; 84(3): 235-70, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23020096

RESUMEN

We analyze the geographic location of 77,451 different Italian surnames (17,579,891 individuals) obtained from the lists of telephone subscribers of the year 1993. By using a specific neural network analysis (Self-Organizing Maps, SOMs), we automatically identify the geographic origin of 49,117 different surnames. To validate the methodology, we compare the results to a study, previously conducted, on the same database, with accurate supervised methods. By comparing the results, we find an overlap of 97%, meaning that the SOMs methodology is highly reliable and well traces back the geographic origin of surnames at the time of their introduction (Late Middle Ages/Renaissance in Italy). SOMs results enables one to distinguish monophyletic surnames from polyphyletic ones, that is surnames having had a single geographic and historic origin from those that started to be in use, with an identical spelling, in different locations (respectively, 76.06% and 21.05% of the total). As we are interested in geographic origins, polyphyletic surnames are excluded from further analyses. By comparing the present location of each monophyletic surname to its inferred geographic origin in late Middle Ages/Renaissance, we measure the extent of the migrations having occurred in Italy since that time. We find that the percentage of individuals presently living in the very area where their surname started to be in use centuries ago is extremely variable (ranging from 22.77% to 77.86% according to the province), thus meaning that self-assessed regional identities seldom correspond to the "autochthony" they imply. For example the upper part of the Thyrennian coast (Northern Latium, Tuscany) has a strong identity but few "autochthonous" inhabitants (∼28%) having been a passageway from the North to the South of Italy.


Asunto(s)
Cromosomas Humanos Y/genética , Emigración e Inmigración/estadística & datos numéricos , Nombres , Filogeografía , Algoritmos , Emigración e Inmigración/historia , Etnicidad , Geografía , Historia Antigua , Humanos , Italia , Redes Neurales de la Computación , Dinámica Poblacional , Análisis Espacial
17.
Hum Biol ; 84(2): 169-214, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22708820

RESUMEN

A recent workshop entitled "The Family Name as Socio-Cultural Feature and Genetic Metaphor: From Concepts to Methods" was held in Paris in December 2010, sponsored by the French National Centre for Scientific Research (CNRS) and by the journal Human Biology. This workshop was intended to foster a debate on questions related to the family names and to compare different multidisciplinary approaches involving geneticists, historians, geographers, sociologists and social anthropologists. This collective paper presents a collection of selected communications.


Asunto(s)
Cultura , Genealogía y Heráldica , Nombres , Filogeografía , Congresos como Asunto , Demografía , Humanos
18.
Am J Phys Anthropol ; 148(3): 327-33, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22460349

RESUMEN

Estimates of mutation rates for the noncoding hypervariable Region I (HVR-I) of mitochondrial DNA vary widely, depending on whether they are inferred from phylogenies (assuming that molecular evolution is clock-like) or directly from pedigrees. All pedigree-based studies so far were conducted on populations of European origin. In this article, we analyzed 19 deep-rooting pedigrees in a population of mixed origin in Costa Rica. We calculated two estimates of the HVR-I mutation rate, one considering all apparent mutations, and one disregarding changes at sites known to be mutational hot spots and eliminating genealogy branches which might be suspected to include errors, or unrecognized adoptions along the female lines. At the end of this procedure, we still observed a mutation rate equal to 1.24 × 10(-6) , per site per year, i.e., at least threefold as high as estimates derived from phylogenies. Our results confirm that mutation rates observed in pedigrees are much higher than estimated assuming a neutral model of long-term HVRI evolution. We argue that until the cause of these discrepancies will be fully understood, both lower estimates (i.e., those derived from phylogenetic comparisons) and higher, direct estimates such as those obtained in this study, should be considered when modeling evolutionary and demographic processes.


Asunto(s)
ADN Mitocondrial/genética , Tasa de Mutación , Linaje , Adulto , Costa Rica , Femenino , Variación Genética/genética , Genética de Población , Humanos , Madres
19.
Am J Hum Biol ; 23(1): 89-99, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21082684

RESUMEN

OBJECTIVES: The Titicaca basin was the cradle of some of the major complex societies of pre-Columbian South America and is today home to three surviving native languages: Quechua, Aymara, and Uro. This study seeks to contribute to reconstructing the population prehistory of the region, by providing a first genetic profile of its inhabitants, set also into the wider context of South American genetic background. METHODS: We report the first mitochondrial DNA first hypervariable segment sequences of native populations of the environs of Lake Titicaca: speakers of Aymara and Quechua, and the "Uros" of the Lake's floating islands. We sampled Aymara speakers from a locality where the Uro language was formerly documented, to check for possible language shift patterns. These data are compared with those for other Amerindian populations, collated from already published sources. RESULTS: Our results uncover the genetic distinctiveness of our formerly Uro but now Aymara-speaking sample, in contrast with a relative homogeneity for all the other Central Andean samples. CONCLUSIONS: The genetic affinities that characterize Central Andean populations are highly consistent with the succession of expansive polities in the region, culminating with the Incas. In the environs of Lake Titicaca, however, one subset of the present day Aymara-speaking population exhibits a peculiar position: perhaps a genetic correlate to their original Uro linguistic lineage (now extinct in the area), tallying with ethnohistorical claims for the distinctiveness of the Uro population. Our results emphasize the need for genetic descriptions to consider the widespread phenomenon of language shift.


Asunto(s)
ADN Mitocondrial/genética , Etnicidad/genética , Indígenas Sudamericanos/genética , Análisis de Varianza , Secuencia de Bases , ADN Mitocondrial/química , Variación Genética , Genética de Población , Haplotipos , Humanos , Lingüística , Datos de Secuencia Molecular , Perú/etnología , Filogenia , Polimorfismo de Longitud del Fragmento de Restricción , Análisis de Secuencia de ADN
20.
Am J Hum Biol ; 23(2): 225-7, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21319252

RESUMEN

OBJECTIVE: To determine if individuals who carry mitochondrial markers which have been previously shown to affect longevity also have differential lifetime reproductive success (LRS). METHODS: We extracted the mtDNA from living subjects residing in Atenas, Costa Rica. Since mtDNA does not recombine, and its probability of mutation is low, we assume that all maternal ancestors of the living subjects have the same mtDNA. We reconstructed the maternal genealogy of the living subjects, so that we have information on the LRS and longevity of the maternal ancestors of the living subjects. We compared the LRS of women who carried the 5178A marker in haplogroup D (associated with decreased longevity) and who carried the 150T polymorphism (associated with increased longevity) with the LRS of controls born in the same half century time period from 1750 to 1939. RESULTS: We found that the LRS of neither group of women with a longevity-associated polymorphism (LAP) differed from the LRS of controls, even if these women differed significantly from the controls in their longevity. CONCLUSIONS: Although LAPS significantly affect longevity, such differential longevity does not result in differential lifetime reproductive success. From an evolutionary perspective, these longevity-associated polymorphisms do not affect the carriers' Darwinian fitness.


Asunto(s)
ADN Mitocondrial/genética , Aptitud Genética , Longevidad/genética , Linaje , Polimorfismo Genético , Costa Rica , Femenino , Haplotipos , Historia del Siglo XVIII , Historia del Siglo XIX , Historia del Siglo XX , Humanos
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