Namesakes or relatives? Approaches to investigating the relationship between Y chromosomal haplogroups and surnames

Population genetics successfully applies surnames as quasi-genetic markers when estimating similarity between populations and calculating a measure of random inbreeding. These calculations are based on an isonomy coefficient which assumes that every surname is monophyletic: that it originated from single common ancestor and all namesakes are therefore relatives. On the other hand, there is a general opinion that a typical Russian surname is polyphyletic: it originated multiple times and most namesakes are therefore not related to each other. Combined studies of Y chromosomes and surnames now allow us to address this issue. In this study, we discuss approaches for statistical evaluation of Y chromosomal haplogroup frequencies in groups of people bearing the same surname (namesakes). We propose an 'Index of Accumulated Haplogroup Frequency', which allows for errors due to random (artifactual) effects increasing a haplogroup frequency in a group of namesakes by subtracting the population frequency of this haplogroup. This population frequency is calculated as the weighted average of the frequencies of this haplogroup in the populations that the carriers of this surname come from. Fom the total sample (comprising 1244 persons from 13 populations of the historical Russian area) we chose 123 persons carrying 14 surnames which were the most frequent in the total sample. Haplogroup frequencies in these 14 "surname" groups were compared with the respective 14 "population" control groups compiled from the total sample as described above. We found that even these widespread surnames exhibit non-random accumulation of specific Y chromosomal haplogroups. More detailed analyses of the relationships between namesakes could be carried out using Y-STR haplotypes rather than Y-SNP haplogroups, and will be the subject of a future study.     

Y-chromosomes and the extent of patrilineal ancestry in Irish surnames

Ireland has one of the oldest systems of patrilineal hereditary surnames in the world. Using the paternal co-inheritance of Y-chromosome DNA and Irish surnames, we examined the extent to which modern surname groups share a common male-line ancestor and the general applicability of Y-chromosomes in uncovering surname origins and histories. DNA samples were collected from 1,125 men, bearing 43 different surnames, and each was genotyped for 17 Y-chromosome short tandem repeat (STR) loci. A highly significant proportion of the observed Y-chromosome diversity was found between surnames demonstrating their demarcation of real and recent patrilineal kinship. On average, a man has a 30-fold increased chance of sharing a 17 STR Y-chromosome haplotype with another man of the same surname but the extent of congruence between the surname and haplotype varies widely between surnames and we attributed this to differences in the number of early founders. Some surnames such as O’Sullivan and Ryan have a single major ancestor, whereas others like Murphy and Kelly have numerous founders probably explaining their high frequency today. Notwithstanding differences in their early origins, all surnames have been extensively affected by later male introgession. None examined showed more than about half of current bearers still descended from one original founder indicating dynamic and continuously evolving kinship groupings. Precisely because of this otherwise cryptic complexity there is a substantial role for the Y-chromosome and a molecular genealogical approach to complement and expand existing sources.     

Excavating past population structures by surname-based sampling: the genetic legacy of the Vikings in northwest England

The genetic structures of past human populations are obscured by recent migrations and expansions and have been observed only indirectly by inference from modern samples. However, the unique link between a heritable cultural marker, the patrilineal surname, and a genetic marker, the Y chromosome, provides a means to target sets of modern individuals that might resemble populations at the time of surname establishment. As a test case, we studied samples from the Wirral Peninsula and West Lancashire, in northwest England. Place-names and archaeology show clear evidence of a past Viking presence, but heavy immigration and population growth since the industrial revolution are likely to have weakened the genetic signal of a 1,000-year-old Scandinavian contribution. Samples ascertained on the basis of 2 generations of residence were compared with independent samples based on known ancestry in the region plus the possession of a surname known from historical records to have been present there in medieval times. The Y-chromosomal haplotypes of these 2 sets of samples are significantly different, and in admixture analyses, the surname-ascertained samples show markedly greater Scandinavian ancestry proportions, supporting the idea that northwest England was once heavily populated by Scandinavian settlers. The method of historical surname-based ascertainment promises to allow investigation of the influence of migration and drift over the last few centuries in changing the population structure of Britain and will have general utility in other regions where surnames are patrilineal and suitable historical records survive.     

Namesakes or relatives? Approaches to investigating the relationship between Y chromosome haplogroups and surnames

Population genetics successfully applies surnames as quasi-genetic markers when estimating similarity between populations and calculating the level of random inbreeding. These calculations are based on the isonymy coefficient, which assumes that every surname is monophyletic, i.e., it originated from a single common ancestor and all namesakes are therefore relatives. On the other hand, there is a general opinion that a typical Russian surname is polyphyletic: it originated multiple times and most namesakes are, therefore, not related to each other. Combined studies of Y chromosomes and surnames now allow us to address this issue. This study discusses approaches to statistical evaluation of Y chromosome haplogroup frequencies in groups of people bearing the same surname (namesakes). The proposed index of accumulated haplogroup frequency eliminates the artifactual effect of a randomly increased haplogroup frequency in namesakes by subtracting its population (expected) frequency from the observed value, while the expected frequency is calculated as the weighted average of the frequencies of this haplogroup in the populations where the surname carriers come from. From the total sample (comprising 1244 persons from 13 populations of the historical Russian area), 123 individuals carrying 14 most frequent surnames were chosen. A comparison of the haplogroup frequencies in these 14 namesake groups and in 14 respective population control groups compiled from the total sample showed that accumulation of certain Y chromosome haplogroups was nonrandom even in carriers of widespread surnames. An analysis of Y-STR haplotypes rather than Y-SNP haplogroups could provide a better insight into relationships between namesakes and will be the subject of further research.     

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.     

Surnames as indicators of European admixture in Andean Indians

The goal of the present report was to determine how well surnames assess the degree of European admixture in urban Aymara. Reflectances, which were measured at three wavelengths (425 nm, 545 nm, and 685 nm) and on two sites (the medial surface of the upper arm and the forehead), were used as genetic markers. The sample consisted of 556 Andean Indians of Aymara ancestry (305 males, 251 females; 10.0–29.9 yr) residing in La Paz, Bolivia (average altitude of about 3600 m). The first component from a principal components analysis was demonstrated to assess the underlying genetics of pigmentation, after controlling for tanning and vascularity, the two primary environmental modifiers of skin color. The scores associated with the first principal component were there-force entered into a discriminant function analysis, which indicated that surnames provide a useful indirect index of the degree of European admixture in urban Aymara. However, these results also suggested that the relationship between, surnames and ethnicity is not equally strong across all surname categories. In particular, the likelihood of correctly predicting surname category from reflectances was about twice that expected by chance alone in individuals with two Aymara or two Spanish surnames but was slightly less than would be expected by chance alone in those with mixed surnames. In addition, the findings of this study suggested that there may be significant genetic differences between rural and urban Aymara.     

In the name of the father: surnames and genetics

Hereditary surnames contain information about relatedness within populations. They have been used as crude indicators of population structure and migration events, and to subdivide samples for epidemiological purposes. In societies that use patrilineal surnames, a surname should correlate with a type of Y chromosome, provided certain assumptions are met. Recent studies involving Y-chromosomal haplotyping and surname analysis are promising and indicate that genealogists of the future could be turning to records written in DNA, as well as in paper archives, to solve their problems.     

Surname distributions and their association with Y-chromosome markers in the Aleutian Islands

We examine surname distribution, origin, and association with Y-chromosome haplogroups in native communities from the Aleutian archipelago. The underlying hypothesis is that surnames and Y-chromosome haplogroups should be associated because both are paternally inherited markers. We used Lasker's coefficient of relationship through isonymy (R(ib) ) to identify the distribution of 143 surnames in the Aleutian Islands. The geographic distribution of surnames was explored both through frequency distribution and through the use of Mantel tests. Multidimensional scaling, chi-square, and Mantel tests were used to examine the relationship between surname and Y-chromosome markers. Overall, we observed that the distribution of surnames in the Aleutian archipelago is culturally driven rather than being one of paternal inheritance. Surnames follow a gradient from east to west, with high frequencies of Russian surnames found in western Aleut communities and high levels of non-Russian surnames found in eastern Aleut communities. A nonsignificant correlation (r = -0.0132; P = 0.436) was found between distance matrices based on haplogroups of the nonrecombining portion of the Y chromosome and surnames, although an association was found between non-Russian surnames and the predominantly non-Russian haplogroups (R1b, I1a, and I).     

Isonymy and the genetic structure of Albanian populations

It is well known that in systems of surname transmission through the paternal line, surnames simulate neutral gene alleles belonging to the Y chromosome. This property of surnames was used to analyze the genetic structure of Albanian populations. Two large samples of surnames belonging to two different periods of time were analyzed. The analysis of indicators of population structure showed that geographical distance has an important effect on surname distribution. It seems that isolation by distance and genetic drift have been still important factors in the determination of the genetic structure of the Albanian population.     

In the name of the migrant father--analysis of surname origins identifies genetic admixture events undetectable from genealogical records

Patrilineal heritable surnames are widely used to select autochthonous participants for studies on small-scale population genetic patterns owing to the unique link between the surname and a genetic marker, the Y-chromosome (Y-chr). Today, the question arises as to whether the surname origin will be informative on top of in-depth genealogical pedigrees. Admixture events that happened in the period after giving heritable surnames but before the start of genealogical records may be informative about the additional value of the surname origin. In this context, an interesting historical event is the demic migration from French-speaking regions in Northern France to the depopulated and Dutch-speaking region Flanders at the end of the sixteenth century. Y-chr subhaplogroups of individuals with a French/Roman surname that could be associated with this migration event were compared with those of a group with autochthonous Flemish surnames. Although these groups could not be differentiated based on in-depth genealogical data, they were significantly genetically different from each other. Moreover, the observed genetic divergence was related to the differences in the distributions of main Y-subhaplogroups between contemporary populations from Northern France and Flanders. Therefore, these results indicate that the surname origin can be an important feature on top of in-depth genealogical results to select autochthonous participants for a regional population genetic study based on Y-chromosomes.     

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.     

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     

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.     

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).     

Isonymic relationships in ethno-social categories (Argentinian colonial period) including illegitimate reproduction

Surnames provide a useful method to study the structure of human populations for which biological data are not available. The isonymic method has had multiple applications, but difficulties emerge when dealing with groups where extramarital reproduction is common and the sample size is small, and even more so when only paternal surnames are taken into account.Therefore, it could be of interest to retain female surnames, including those of unmarried mothers. This study was carried out using all birth records froman Argentinian population in the colonial period, which was characterized by the presence of different ethno-social groups (Spanish, Indian and 'Mestizo'or mixed Spanish-Indian) and various reproductive patterns regarding legitimacy. Coefficient of relationship by isonymy (Ri) kinship matrices between geographical populations were obtained, and the results derived from sets of surnames (paternal, maternal of legitimate and illegitimate children,and all surnames in the registers) compared. The results show similar surname distribution regardless of the set of surnames and group considered.Kinship Ri matrices using paternal surnames, maternal surnames of legitimate children, maternal surnames of illegitimate children, and the set of whole surnames showed the same relationships among populations, indicating a similar pattern for Spanish, Indian and Mixed ethno-social groups. Mantel test correlation between all pairs of matrices was significant in all different ethno-social groups. The results suggest that in populations with high illegitimacy, such as that studied here, it is possible to include maternal surnames, even corresponding to single mothers, in order to consider total reproduction and therefore maximize sample size.     

Surnames in the Study of Human Biology

Use of surname analysis in human population biology depends on surnames being inherited like genes. In societies that meet this condition, communities with a few surnames at high frequency are the more inbred ones, and marriages between persons of the same surname can be used to estimate rates of inbreeding. Furthermore, the degree of commonality of the surnames of two communities estimates their biological relationship provided that any two persons of the same surname derived it from a common ancestor and that virilocal and uxorilocal migration is equal. Although the assumptions are only partially met, the surname method yields results which correlate with the amount of marital migration and with geographical and historical features. Rare surnames meet the assumptions better than common ones. Documents, both old and new, yield surnames of large numbers of people which can easily be analyzed to show the cumulative effect of marital migration since the establishment of surnames (in England in the Middle Ages). Surnames thus serve to delineate the breeding structure of some human populations over a longer span of time than is usually possible with pedigrees, over a more definite span of time than in genetic studies, and more easily in broad surveys than alternative methods . [isonymy, surnames, inbreeding, coefficient of relationship, England]     

Thomas Jefferson's Y chromosome belongs to a rare European lineage

We have characterized the Y chromosome carried by President Thomas Jefferson, the general rarity of which supported the idea that he, or a patrilineal relative, fathered the last son of his slave Sally Hemings. It belongs to haplogroup K2, a lineage representing only approximately 1% of chromosomes worldwide, and most common in East Africa and the Middle East. Phylogenetic network analysis of its Y-STR (short tandem repeat) haplotype shows that it is most closely related to an Egyptian K2 haplotype, but the presence of scattered and diverse European haplotypes within the network is nonetheless consistent with Jefferson's patrilineage belonging to an ancient and rare indigenous European type. This is supported by the observation that two of 85 unrelated British men sharing the surname Jefferson also share the President's Y-STR haplotype within haplogroup K2. Our findings represent a cautionary tale in showing the difficulty of assigning individual ancestry based on a Y-chromosome haplotype, particularly for rare lineages where population data are scarce.     

Relationships among companies of militia in the colony of New York in 1760 estimated by an analysis of their surnames

Abstract

Surname, analysis, a technique to estimate genetic relatedness, is applied here to differences within and between eight militia companies (N=782) mustered for New York Colony in 1760. Universal service laws of the time imply that militias are unbiased community samples. Colonial American populations are of interest due to their heterogeneous migrant origins, balanced by effects of large kin groups. The surname of each militiaman was checked for identity to that of all others within and between the eight companies. Assuming surnames derive from common ancestry, fractions of name identity index relatedness. Within‐company relatedness is high, below only that found in genetic isolates, probably due to enlistments together of kinsmen. Between‐company relatedness is the lowest yet recorded, apparently because of the diverse origins of these populations.     

High Y-chromosomal diversity and low relatedness between paternal lineages on a communal scale in the Western European Low Countries during the surname establishment

There is limited knowledge on the biological relatedness between citizens and on the demographical dynamics within villages, towns and cities in pre-17th century Western Europe. By combining Y-chromosomal genotypes, in-depth genealogies and surname data in a strict genetic genealogical approach, it is possible to provide insights into the genetic diversity and the relatedness between indigenous paternal lineages within a particular community at the time of the surname adoption. To obtain these insights, six Flemish communities were selected in this study based on the differences in geography and historical development. After rigorous selection of appropriate DNA donors, low relatedness between Y chromosomes of different surnames was found within each community, although there is co-occurrence of these surnames in each community since the start of the surname adoption between the 14th and 15th century. Next, the high communal diversity in Y-chromosomal lineages was comparable with the regional diversity across Flanders at that time. Moreover, clinal distributions of particular Y-chromosomal lineages between the communities were observed according to the clinal distributions earlier observed across the Flemish regions and Western Europe. No significant indication for genetic differences between communities with distinct historical development was found in the analysis. These genetic results provide relevant information for studies in historical sciences, archaeology, forensic genetics and genealogy.