Do surname differences mirror dialect variation?

Our focus in this paper is the analysis of surnames, which have been proven to be reliable genetic markers because in patrilineal systems they are transmitted along generations virtually unchanged, similarly to a genetic locus on the Y chromosome. We compare the distribution of surnames to the distribution of dialect pronunciations, which are clearly culturally transmitted. Because surnames, at the time of their introduction, were words subject to the same linguistic processes that otherwise result in dialect differences, one might expect their geographic distribution to be correlated with dialect pronunciation differences. In this paper we concentrate on the Netherlands, an area of only 40,000 km2, where two official languages are spoken, Dutch and Frisian. We analyze 19,910 different surnames, sampled in 226 locations, and 125 different words, whose pronunciation was recorded in 252 sites. We find that, once the collinear effects of geography on both surname and cultural transmission are taken into account, there is no statistically significant association between the two, suggesting that surnames cannot be taken as a proxy for dialect variation, even though they can be safely used as a proxy for Y-chromosome genetic variation. We find the results historically and geographically insightful, hopefully leading to a deeper understanding of the role that local migrations and cultural diffusion play in surname and dialect diversity.     

New method for surname studies of ancient patrilineal population structures, and possible application to improvement of Y-chromosome sampling

Several studies showed that surnames are good markers to infer patrilineal genetic structures of populations, both on regional and microregional scales. As a case study, the spatial patterns of the 9,929 most common surnames of the Netherlands were analyzed by a clustering method called self-organizing maps (SOMs). The resulting clusters grouped surnames with a similar geographic distribution and origin. The analysis was shown to be in agreement with already known features of Dutch surnames, such as 1) the geographic distribution of some well-known locative suffixes, 2) historical census data, 3) the distribution of foreign surnames, and 4) polyphyletic surnames. Thus, these results validate the SOM clustering of surnames, and allow for the generalization of the technique. This method can be applied as a new strategy for a better Y-chromosome sampling design in retrospective population genetics studies, since the idenfication of surnames with a defined geographic origin enables the selection of the living descendants of those families settled, centuries ago, in a given area. In other words, it becomes possible to virtually sample the population as it was when surnames started to be in use. We show that, in a given location, the descendants of those individuals who inhabited the area at the time of origin of surnames can be as low as approximately 20%. This finding suggests 1) the major role played by recent migrations that are likely to have distorted or even defaced ancient genetic patterns, and 2) that standard-designed samplings can hardly portray a reliable picture of the ancient Y-chromosome variability of European populations.     

Geographical distribution of some Danish surnames: reflections of social and natural selection.

Geographical differences in the frequencies of eight common surnames in Jutland (Denmark) are analysed using data from telephone directories of 121 exchanges. All the names showed a significant geographical surplus variance, which was divided into trend and patchiness components reflecting the history of the names. The surplus variance of surnames with restricted areas of origin was dominated by a large trend component; for surnames with an originally more even distribution, the patchiness component was dominant. The patterns of distribution were affected by processes which modelled natural selection with linkage disequilibrium. The combined patchiness within the clusters of exchanges gave information about patterns of local migration and level of social integration in the communities. Areas situated in boundary regions show high levels of patchiness.     

Relationships among given names in the Scilly Isles

The pseudo-genetic analysis of given names shows that, in the Scilly Isles, coefficients of relationship of first names are similar on St Mary's, the Outer Isles, and in the total sample of 5666 individuals married there in two and a half centuries. Comparable coefficients of relationship of a sample of 1658 given names in marriages in England and Wales in 1975 are considerably smaller, but similar within and between districts. The coefficients of relationship of given names on the Scilly Isles decreases during the 19th and especially the 20th centuries in parallel with decreases in random relationship from surnames. The genetic versus cultural-linguistic factors cannot be distinguished in the temporal variation in names, but the geographic differentiation virtually always reported in surnames is not present in these examples of given names and the geographic pattern in the surnames thus seems to result from the hereditary aspect of surnames. This result supports the validity of use of surnames in models of human genetic geography.     

Cultural factor in the geographic distribution of personal names: pseudogenetic analysis of first names used to estimate the cultural component of coefficients of relationship by isonymy

By applying to given names formulations for analyzing the genetics of surname distributions, under certain assumptions one can separate the genetic components from the cultural components of surname distributions. Geographic distributions of surnames regularly yield larger coefficients of relationship or kinship within local populations than between them: for instance, Ri = 75 x 10(-5) within a local area in England but the Ri of those villages with all of England and Wales is 42 x 10(-5). On the contrary, the first names in an English and Welsh sample give essentially the same pseudocoefficient (based on first names) within registration districts (Ri = 354 x 10(-5) as between districts (Ri = 370 x 10(-5). Thus the decrease with distance of the coefficients based on surnames can be ascribed to the genetic component according to the Malécot principle, assuming that the first names are chosen in the same way as the surnames originated and consequently that the cultural component of surname distributions is no more localized than the distribution of given names (in this sample not at all).     

Autochthony and HLA frequencies in the Netherlands: when surnames are useless markers

To study the genetic variability of the HLA loci A, B, DR, and DQ in the Netherlands, we analyzed more than 13,000 typings provided by the Dutch National Reference Laboratory for Histocompatibility. To investigate any possibly existing population structure, we subdivided the typings by the geographic location of residency of donors and by the historical belonging of their surnames to given provinces. Concerning possible geographic patterns, we found no significant differences between the four provinces examined (North Holland, South Holland, Utrecht, Zeeland). To assess whether such a negative result was related to recent immigration to the area (the richest of the country) that erased possible preexisting patterns of HLA diversity, we reprocessed the database according to the surnames of HLA donors. We obtained two groups: (1) those having a surname typical of the four provinces they inhabit and (2) those with surnames coming from elsewhere. Such an analysis was made possible because of the availability of a database concerning the geographic origin of most Dutch surnames. Even with this surname-based approach, no major differences were found. We conclude that either the western part of the Netherlands was genetically homogeneous before the official introduction of Dutch surnames two centuries ago by Napoleon or surnames have no power in dissecting HLA variability; that is, such variability is the result of recombination phenomena that surnames cannot mirror because they are transmitted virtually unchanged generation after generation. A comparable study by other investigators recommended the use of family names to identify rare HLA haplotypes in France, but now, concerning the Netherlands, we find opposite results. We suggest that a few typing centers may be sufficient to type bone marrow donors, because HLA genetic differences between the different provinces of the Netherlands are extremely low. To maximize the number of donors, such centers should be located in areas providing the easiest access to the largest population of possible donors, thus disregarding the search for a local variability that we did not find.     

Correlations between Isonymy Parameters

Several parameters of genetic and anthropological interest are commonly estimated in the analysis of the surnames' distribution in human populations. Among these parameters, the most important for population structure is unbiased Isonymy, equivalent to 4 times the value of F_st, the random component of inbreeding in a group. Fisher's α estimates the wealth of surnames in a group, and Karlin-McGregorv is considered proportional to migration rates. Recently, other parameters like Entropy and Redundance of the surname's distribution were introduced in the analysis and estimated. In the present work, the parameters obtained through isonymy analysis of 759,500 telephone users in 379 Communes of Sicily are correlated with variables such as sample size, population size and density, and number of surnames in the Commune. In Sicily, the parameters or their logarithm are Gammadistributed. It is observed that the number of surnames is strongly correlated with most parameters or with their logarithm, and that it is in turn strongly correlated with sample size.     

Sicilian provinces: population subdivisions revealed by surname frequencies

The Sicilian population has a complex history of colonization and invasions that have influenced the genetic composition of the nine provinces of the island. Because surnames are patrilineally inherited, they simulate a Y-chromosome nonrecombinant genetic locus. We used surname data and a specific sampling strategy to describe the major subdivisions in each province and for the whole island of Sicily. The high number of families per surname in two provinces can be related to inbreeding as a result of founder events. Each province shows a major division, which, according to local historical events, likely represents cultural and probably genetic differences between east and west, between north and south, or between the inner regions and the coastal area. On the island level surnames reproduce the same separation, obtained by others with genes, of the eastern area from the western area. The separation is attributed to Greek influence in the east and to Phoenician-Carthaginian-Norman influence in the west. This separation crosses the two central provinces of Agrigento and Caltanissetta.     

Surnames and cancer genes

The surname analysis of over 40,000 Wisconsin cancer mortalities for the period 1979 through 1985 partially reveals the relative genetic component of various major cancers. The surname frequencies and frequency distributions indicate that both tumor-promoting and tumor-suppressing genes may be involved. A number of cancers exhibit some probable genetic component, but genetic involvement seems marked in male and female leukemia and male lung cancer. Evidence is found for autosomal and sex-linked, dominant and recessive patterns. Most surprising is the strong evidence for tumor-suppressing genes for most cancers. Clustering of surnames across cancers evinces a number of Wisconsin surnames that may be involved in a cancer family syndrome.     

Clines, clusters, and the effect of study design on the inference of human population structure

Previously, we observed that without using prior information about individual sampling locations, a clustering algorithm applied to multilocus genotypes from worldwide human populations produced genetic clusters largely coincident with major geographic regions. It has been argued, however, that the degree of clustering is diminished by use of samples with greater uniformity in geographic distribution, and that the clusters we identified were a consequence of uneven sampling along genetic clines. Expanding our earlier dataset from 377 to 993 markers, we systematically examine the influence of several study design variables—sample size, number of loci, number of clusters, assumptions about correlations in allele frequencies across populations, and the geographic dispersion of the sample—on the “clusteredness” of individuals. With all other variables held constant, geographic dispersion is seen to have comparatively little effect on the degree of clustering. Examination of the relationship between genetic and geographic distance supports a view in which the clusters arise not as an artifact of the sampling scheme, but from small discontinuous jumps in genetic distance for most population pairs on opposite sides of geographic barriers, in comparison with genetic distance for pairs on the same side. Thus, analysis of the 993-locus dataset corroborates our earlier results: if enough markers are used with a sufficiently large worldwide sample, individuals can be partitioned into genetic clusters that match major geographic subdivisions of the globe, with some individuals from intermediate geographic locations having mixed membership in the clusters that correspond to neighboring regions.     

Isonymy and isolation by distance in the Netherlands

The isonymy structure of the Netherlands was studied using the surname distribution of 2.4 million private telephone users selected from a 1996 commercial CD-ROM containing the names of 6.3 million users in the country. The users were distributed in 226 towns selected on a geographic basis to form an approximately regular grid throughout the Netherlands. Names of telephone users in each town were downloaded from the CD-ROM, with private users being selected for inclusion in the analysis. The shortest linear distance between several nearest neighboring towns was less than 2 km (e.g., Kampen and Ijsselmuiden, Krommen and Zaandijk, Hendrikdo and Papendrecht) and the longest distance was 326 km (Delfzijl and Oostburg ZL). The number of different surnames revealed by the analysis was 126,485. Lasker's distance, the negative value of the logarithm of isonymy between localities, was found to be significantly correlated with linear geographic distance, with r = 0.47 +/- 0.006. A dendrogram built using the matrix of isonymy distances, using the nearest neighbor-joining method, separates the Dutch towns into several clusters, most of them correlated with traditional Dutch regions. Comparisons with the results of previous analyses of the structure of other European countries are given. From the present analysis, isolation by distance emerges clearly, and it is relevant, although much weaker than in Switzerland, Austria, Italy, and Germany. The random component of inbreeding estimated from isonymy indicates a considerable degree of homogeneity in the Netherlands.     

The Surname Space of the Czech Republic: Examining Population Structure by Network Analysis of Spatial Co-Occurrence of Surnames

In the majority of countries, surnames represent a ubiquitous cultural attribute inherited from an individual''s ancestors and predominantly only altered through marriage. This paper utilises an innovative method, taken from economics, to offer unprecedented insights into the “surname space” of the Czech Republic. We construct this space as a network based on the pairwise probabilities of co-occurrence of surnames and find that the network representation has clear parallels with various ethno-cultural boundaries in the country. Our inductive approach therefore formalizes a simple assumption that the more frequently the bearers of two surnames concentrate in the same locations the higher the probability that these two surnames can be related (considering ethno-cultural relatedness, common co-ancestry or genetic relatedness, or some other type of relatedness). Using the Czech Republic as a case study this paper offers a fresh perspective on surnames as a quantitative data source and provides a methodology that can be easily incorporated within wider cultural, ethnic, geographic and population genetics studies already utilizing surnames.     

Given name relationships support surname 'genetics': a note and correction.

Analysis of a further four samples of first names in the index of marriages registered in England and Wales in the first 3 months of 1975 support the claim that there is no significant difference of 'between' versus 'within' registration district Ri. Since given names show none of the localisation seen in surnames, the surname geography is ascribable to genetic rather than cultural factors of personal naming. The correct formulations for coefficient of relationship by isonymy are given.     

Surname analysis of the Corsican population reveals an agreement with geographical and linguistic structure

The surname is a cultural trait that is extremely useful for historical and linguistic studies and can effectively be used as a genetic marker. In many human populations the surname is inherited in the paternal lineage, and can therefore be considered a marker for the Y chromosome. In this study, surnames were recorded from the white pages of telephone directories in current use in Corsica in 1993. All surnames present in thirteen villages scattered over the whole island and covering the main historical regions were transcribed. Surname variability was found to be higher in coastal villages, and lower in more isolated communities. The isonymy detected among the thirteen villages allowed the calculation of kinship values, visualized in a tree showing two main clusters, one referring to the northern villages and one encompassing the villages of the south. The pattern reflects the administrative division of the island, with the exception of Vico, which belongs to the southern administrative region but is geographically close to the northern villages, and Ghisoni, which belongs to the northern district but is more similar to the village of Bastelica in the southern district. The data presented here show a structure in the surname distribution that is in substantial agreement with the geographical patterns. The kinship values are consistent with a moderated gene flow among villages producing a surname structure according to the geographic features of the territory.     

Russian genofond. Genogeography of surnames

Surnames are traditionally used in population genetics as "quasi-genetic" markers (i.e., analogs of genes) when studying the structure of the gene pool and the factors of its microevolution. In this study, spatial variation of Russian surnames was analyzed with the use of computer-based gene geography. Gene geography of surnames was demonstrated to be promising for population studies on the total Russian gene pool. Frequencies of surnames were studied in 64 sel'sovets (rural communities; a total of 33 thousand persons) of 52 raions (districts) of 22 oblasts (regions) of the European part of Russia. For each of 75 widespread surnames, an electronic map of its frequency was constructed. Summary maps of principal components were drawn based on all maps of individual surnames. The first 5 of 75 principal components accounted for half of the total variance, which indicates high resolving power of surnames. The map of the first principal component exhibits a trend directed from the northwestern to the eastern regions of the area studied. The trend of the second component was directed from the southwestern to the northern regions of the area studied, i.e., it was close to latitudinal. This trend almost coincided with the latitudinal trend of principal components for three sets of data (genetic, anthropological, and dermatoglyphical). Therefore, the latitudinal trend may be considered the main direction of variation of the Russian gene pool. The similarity between the main scenarios for the genetic and quasi-genetic markers demonstrates the effectiveness of the use of surnames for analysis of the Russian gene pool. In view of the dispute between R. Sokal and L.L. Cavalli-Sforza about the effects of false correlations, the maps of principal components of Russian surnames were constructed by two methods: through analysis of maps and through direct analysis of original data on the frequencies of surnames. An almost complete coincidence of these maps (correlation coefficient rho = 0.96) indicates that, taking into account the reliability of the data, the resultant maps of principal components have no errors of false correlations.     

Genetic structure, self-identified race/ethnicity, and confounding in case-control association studies

We have analyzed genetic data for 326 microsatellite markers that were typed uniformly in a large multiethnic population-based sample of individuals as part of a study of the genetics of hypertension (Family Blood Pressure Program). Subjects identified themselves as belonging to one of four major racial/ethnic groups (white, African American, East Asian, and Hispanic) and were recruited from 15 different geographic locales within the United States and Taiwan. Genetic cluster analysis of the microsatellite markers produced four major clusters, which showed near-perfect correspondence with the four self-reported race/ethnicity categories. Of 3,636 subjects of varying race/ethnicity, only 5 (0.14%) showed genetic cluster membership different from their self-identified race/ethnicity. On the other hand, we detected only modest genetic differentiation between different current geographic locales within each race/ethnicity group. Thus, ancient geographic ancestry, which is highly correlated with self-identified race/ethnicity--as opposed to current residence--is the major determinant of genetic structure in the U.S. population. Implications of this genetic structure for case-control association studies are discussed.     

Portuguese migration to the Canary Islands: an analysis based on surnames

As a part of a wider analysis of population and genetic exchange between Spain and Portugal, the long-term pattern of Portuguese immigration to the Canary Islands was studied by means of the frequency of Portuguese surnames. A database of 1,995,833 individuals was obtained from the Spanish National Statistics Institute (2006). Among the 826 most frequent surnames to appear, 79 surnames of Portuguese origin were selected. The distribution of these surnames by municipalities and islands, the Fisher index of diversity, and the Lasker inter-population relationship coefficients R(ij) were considered. These coefficients were inter-correlated and correlated with other variables that could have influenced the distribution of surnames. From the observed distribution of the frequency of surnames, a non-random migration pattern conditioned by economic factors was found. The greatest diversity of surnames existed in cane cultivating areas after the first arrival of Portuguese immigrants. A later dispersion of surnames among islands was correlated with the inter-island geographic distances. In some islands the arrival of new immigrants continued due to their strategic location within the Canary archipelago. The Canary Islands reveal a high frequency and diversity of Portuguese surnames. The results also prove a heterogeneous distribution of these surnames throughout the archipelago. In contrast to the Portuguese archipelagos, some Canary localities have received immigrants continuously because of their economic importance in sugar cane cultivation and strategic geographic location on the maritime routes to Africa and America.     

宋朝中国人的姓氏分布与群体结构分化

姓氏是一种十分有用的文化遗传因子,它的传递方式类似于Ｙ染色体的表现。１０００年前宋朝（公元９６０￣１１７９年）中国人姓氏频率的分布,是一组十分吻合Ｋａｒｌｉｎ－ＭｃＧｒｅｇｏｒ的中性等位基因分布理论的随机数据。１６个省区的姓氏种类丰度的相对参数α和迁移率的相对参数ｖ的分析,反映了这一时期的中国人群的迁移和人群间混合的程度。姓氏遗传距离和现状聚类图的分析,表明在１０００年前的宋朝中国人群已经形成了南     

Genetic signatures of coancestry within surnames

Surnames are cultural markers of shared ancestry within human populations. The Y chromosome, like many surnames, is paternally inherited, so men sharing surnames might be expected to share similar Y chromosomes as a signature of coancestry. Such a relationship could be used to connect branches of family trees, to validate population genetic studies based on isonymy, and to predict surname from crime-scene samples in forensics. However, the link may be weak or absent due to multiple independent founders for many names, adoptions, name changes and nonpaternities, and mutation of Y haplotypes. Here, rather than focusing on a single name, we take a general approach by seeking evidence for a link in a sample of 150 randomly ascertained pairs of males who each share a British surname. We show that sharing a surname significantly elevates the probability of sharing a Y-chromosomal haplotype and that this probability increases as surname frequency decreases. Within our sample, we estimate that up to 24% of pairs share recent ancestry and that a large surname-based forensic database might contribute to the intelligence-led investigation of up to approximately 70 rapes and murders per year in the UK. This approach would be applicable to any society that uses patrilineal surnames of reasonable time-depth.     

An Ancient Mediterranean Melting Pot: Investigating the Uniparental Genetic Structure and Population History of Sicily and Southern Italy

Due to their strategic geographic location between three different continents, Sicily and Southern Italy have long represented a major Mediterranean crossroad where different peoples and cultures came together over time. However, its multi-layered history of migration pathways and cultural exchanges, has made the reconstruction of its genetic history and population structure extremely controversial and widely debated. To address this debate, we surveyed the genetic variability of 326 accurately selected individuals from 8 different provinces of Sicily and Southern Italy, through a comprehensive evaluation of both Y-chromosome and mtDNA genomes. The main goal was to investigate the structuring of maternal and paternal genetic pools within Sicily and Southern Italy, and to examine their degrees of interaction with other Mediterranean populations. Our findings show high levels of within-population variability, coupled with the lack of significant genetic sub-structures both within Sicily, as well as between Sicily and Southern Italy. When Sicilian and Southern Italian populations were contextualized within the Euro-Mediterranean genetic space, we observed different historical dynamics for maternal and paternal inheritances. Y-chromosome results highlight a significant genetic differentiation between the North-Western and South-Eastern part of the Mediterranean, the Italian Peninsula occupying an intermediate position therein. In particular, Sicily and Southern Italy reveal a shared paternal genetic background with the Balkan Peninsula and the time estimates of main Y-chromosome lineages signal paternal genetic traces of Neolithic and post-Neolithic migration events. On the contrary, despite showing some correspondence with its paternal counterpart, mtDNA reveals a substantially homogeneous genetic landscape, which may reflect older population events or different demographic dynamics between males and females. Overall, both uniparental genetic structures and TMRCA estimates confirm the role of Sicily and Southern Italy as an ancient Mediterranean melting pot for genes and cultures.