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I Barrai

Publications and source records attributed to I Barrai.

At least 19 recordsLinked to original sources
PubMed2005

Surnames and dialects in France: population structure and cultural evolution.

To study the isonymy structure of France as related to local language variations, the surname distributions of 6.03 million telephone users registered for the year 2002 were analysed in the 21 conterminous regions, their 94 departments and in 809 towns of the Country. For regions and departments the differences among local dialects were quantified according to the dialecto-metrization of the Atlas Linguistique Français. We found that Lasker's distance between regions was correlated with geographic distance with r=0.692+/-0.040, while Euclidean (r=0.546+/-0.058) and Nei's (r=0.610+/-0.048) distances were less correlated. Slightly lower correlations were observed for departments. Also, dialectometric distance was correlated with geography (r=0.582+/-0.069 for regions and r=0.617+/-0.015 for departments). The correlations between Lasker and dialectometric matrix distances for regions and departments are r=0.625+/-0.046 and 0.544+/-0.014, respectively, indicating that the common cause generating surname and language diversity accounts for about 35% of the differentiation. Both Lasker and dialectometric distances identify very similar boundaries between Poitou, Centre, Bourgogne and Franche Comptée at the North, and Aquitaine, Limousin, Auvergne, Rhône-Alpes in the South. Average Fisher's alpha for France was 7877 the highest value observed for the European countries studied to date. The size of alpha in most French towns indicates considerable recent immigration.

Cultural Evolution↗
PubMed2005

Surnames in Argentina: a population study through isonymy.

In order to study the isonymic structure of Argentina, the surname distributions of 22.6 million electors registered for the year 2001 were analyzed in the 24 districts (distritos) and 541 municipalities (municipios) of the country. The number of different surnames found was 414,441. Matrices of isonymic distances between districts were constructed and tested for correlation with the geographic distance between the capital towns of the districts. We found that, for the whole of Argentina, Euclidean distance was correlated with the log of geographic distance (r=0.480+/- 0.067). A dendrogram of the 24 regions was built from the matrix of Euclidean distances, using the UPGMA method. The clusters identified by the dendrogram are coincident with conterminous geographical regions of the country. Random inbreeding calculated from isonymy, F(ST), was highest in La Rioja, Corrientes, and Santiago del Estero. It was lowest in the area of Buenos Aires and in the north-central region of Santa Fé. Average Fisher's alpha for municipalities was 358; for districts, it was 422; and for Argentina as a unit, it was 602. The geographical distribution of alpha in 541 municipalities, high in the east and lower in the west of the country, is compatible with the settlement in the 20th century of subsequent waves of immigrants moving from the North Atlantic coast toward the foot of the Andes and toward the south. The present structure of Argentina indicates that migration dominates over drift.

Argentina↗
PubMed2004

Isolation by language and distance in Belgium.

The isonymy structure of trilingual Belgium was studied using the surname distributions for 1,118,004 private telephone users. The users were distributed in 77 Flemish, 76 French, and 3 German speaking towns, selected on a geographic basis to form an approximately regular grid over Belgium. Lasker's distance was found to be considerably higher between languages than within languages. For the whole of Belgium, irrespective of language, it was highly correlated with linear geographic distance, with r = 0.721+/-0.014, which is the highest correlation observed in European countries to date. Within Belgium and within languages, the correlation was highest among the Flemish (r = 0.878 +/- 0.007), and lowest among the French (r = 0.631+/-0.020). Isolation by distance in Belgium is the highest we have found in Europe, and as high as in Switzerland where the different languages are separated by geographical barriers. This is not the case in Belgium, so that the considerable isolating power of languages emerges clearly from the present analysis. From the comparison of Lasker's distance between (9.48) and within (8.16) languages, and from its regression over geographic distance (b = 0.01206), it was possible to establish a quantitative relationship between the isolating power of languages and that of geographic distance as (9.48-8.16)/0.01206 = 109 kilometres. This transformation of language distance into an equivalent geographic distance, given here for Belgium, can be applied to any similar geo-linguistic situation.

Belgium↗
PubMed2003

The names of Spain: a study of the isonymy structure of Spain.

In order to estimate the isonymy structure of Spain, we studied surname distribution in 283 Spanish towns based on 3.625 million telephone users selected from 6.328 million users, downloaded from a commercial CD-ROM which contains all 13 million users in the country. Since in Spain the surname is made by the paternal and the maternal surname, it was possible to classify surnames according to parental origin. Two matrices of isonymy distances, one for paternal and one for maternal surnames, were constructed and tested for correlation with geographic distance. For the whole of Spain, Euclidean distance was significantly but weakly correlated with geographic distance both for paternal and maternal surnames, with r = 0.205 +/- 0.013 and r = 0.263 +/- 0.012, respectively. Two dendrograms of the 283 sampled towns were built from the two matrices of Euclidean distance. They are largely colinear. Four main clusters identified by the dendrograms are correlated with geography. Given the surname structure of Spain, we were able to calculate from isonymy and for each town 1). total or expressed inbreeding, 2). random or expected inbreeding, and 3). local inbreeding. Total inbreeding, F(IT), was highest in the North Atlantic regions and lowest along the Mediterranean Coast. The lowest levels were found in Andalusia, Catalunyia, Valencia, and Navarra. Random inbreeding, F(ST), had a similar geographical pattern. Local inbreeding, F(IS), was relatively uniform in the whole of Spain. In towns, random inbreeding dominates over local inbreeding. From the analysis, it emerges that the northwestern area of Spain is the most inbred.

Female↗
PubMed2002

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.

CD-ROM↗
PubMed2001

Isonymy structure of USA population.

The isonymy structure of the 48 states of the continental United States of America was studied using the surname distributions of 18 million telephone users, distributed in 247 towns. The shortest linear distance between nearest neighbor towns included in the sample was 12.0 km. The largest distance was 4,577 km. The number of different surnames found in the whole analysis was 899,585. Lasker's distance was found to be significantly but weakly correlated with the geographic distance, with r = 0.21 +/- 0.01. A dendrogram of the 48 states was built from the matrix of isonymy distances: it divides the US into several clusters, in general correlated with geography. A notable exception is California and New Jersey, which cluster together. Wisconsin is separated from all other states. An important cluster is formed by Texas, Colorado, New Mexico, Nevada, and Arizona, together with Illinois and Florida. It was observed that Hispanic surnames are among the most frequent in Illinois, as they are in New Jersey and California. No main distinction among the states clearly attributable to surnames of French origin was detected; however, New Hampshire, Vermont, and Maine which have a considerable number of these surnames belong to the same northeastern cluster. From the present analysis, the great mobility of the US population emerges clearly, and it seems relevant that the practical absence of isolation by distance is seen also considering only small towns. It appears that groups of different origin are well-mixed over the whole area of the United States. The values of isonymy indicate that the south-central area of the USA has the highest level of inbreeding. In fact, the heterogeneity in surname composition is greater in the coastal areas, particularly on the East Coast, than anywhere else in the USA.

Emigration and Immigration↗
PubMed2001

Genetic structures and linguistic boundaries in Italy: a microregional approach.

The amount of genetic data (sequences, gene frequencies, and isonymy) available for the Province of Ferrara, Italy, makes this area one of the world's best known. In an effort to infer the underlying demographic processes, we studied the province's population structure by comparing geological, palaeoclimatic, archeological, historical, and linguistic data. This multilevel approach allowed us to date some characteristics of the population structure from prehistoric times to the Roman and Middle Ages, and to detect overlapping biological, cultural, and geographic boundaries. To detect linguistic boundaries within this area we turned pronunciation differences into phonetic notation. We then computed pairwise distances by using methods for multiple genetic sequence analysis, in order to obtain a distance matrix of the overall pronunciation variability. This approach enabled us to test the association among linguistic, geographical, and genetic distance matrices using the same statistical tests. Results indicate that demographic phenomena can be traced in an area as small as the Province of Ferrara and that, on a microregional scale, recent events may have influenced important aspects of the overall genetic variation.

Genetics, Population↗
PubMed2000

Allele and genotype frequencies for D1S80 and 3'APOB in Recanati, Central Italy.

The VNTR 3'APOB and D1S80 loci were studied in a sample of 179 individuals living in the Recanati Area (Central Italy). For 3'APOB, we found 34 genotypes and 11 alleles. The system was in Hardy-Weinberg equilibrium. The observed and expected heterozygosity were 0.788 and 0.798 respectively. The discrimination power was 0.96, the a-priori paternity exclusion power was 0.619 and the polymorphism information content was 0.773. For D1S80, we found 45 genotypes and 18 alleles. The system deviated significantly from Hardy-Weinberg equilibrium. The observed and expected heterozygosity were 0.696 and 0.790 respectively. The discrimination power was 0.96, the a-priori paternity exclusion power was 0.617 and PIC was 0.767. The Recanati sample was compared with the general Italian frequencies for the 3'APOB locus. A difference of borderline significance was detected (P = 0.04). For D1S80, the sample was compared with a sample from Southern Italy and no significant difference was detected.

Alleles↗
PubMed1999

Isonymy and isolation by distance in Italy.

The isonymy structure of Italy was studied using the surname distribution of 5,043,580 private telephone users selected from a 1996 commercial CD-ROM that contains all 24 million users in the country. The users were distributed in 123 towns selected on a geographic basis. The 123 towns were either on the main communication roads of the country or at the ends of such roads. The shortest distance between nearest neighbor towns was 5.3 km (Carrara and Massa), and the largest distance was 1,136 km (Aosta and Castrignano del Capo). The number of different surnames found in the whole analysis was 215,623. Lasker's distance, the negative value of the logarithm of random isonymy between localities, was linearly and significantly correlated with the logarithm of geographic distance, with r = 0.63 +/- 0.008. A dendrogram was built from the matrix of isonymy distances, using UPGMA. It separates the Italian towns into 5 main clusters: 1 in the southern portion of the country, a second cluster toward the center, and 3 in the northern area of Italy. Within each cluster small subclusters with specific geographic distributions could be related to regional borders. Comparisons with the results of a previous analysis of Switzerland and Germany's structures are given. From the present analysis isolation by distance emerges clearly, although it is less strong than in Switzerland and stronger than in Germany. The random component of inbreeding estimated from isonymy indicates that the southern area of Italy is on average more inbred than the northern area. In fact, the heterogeneity is greater in the northern area, particularly in the plain of the Po River, than anywhere else in Italy.

Cluster Analysis↗
PubMed1998

Isonymy and isolation by distance in Germany.

The isonymy structure of Germany was studied using the surname distributions of 5,150,310 private telephone users selected from 39,000,000 users registered in a 1996 commercial CD-ROM, which contains all telephone users in the country. The users were distributed in 106 towns selected on a geographic basis. Germany was subdivided into 50 adjacent rectangles, each 115 x 80 km, and at least the largest town in the rectangle was selected for study; the private telephone users in that district were downloaded from the CD-ROM and included in the analysis. The shortest distance between nearest neighbor towns was 10.7 km (Travemunde and Lübeck), and the largest distance was 69.8 km (Meppen and Osnabruck). The number of different surnames found in the whole analysis was 462,526. Lasker's distance, the negative value of the logarithm of isonymy between localities, was found to be linearly and significantly correlated with geographic distance (r = 0.51 +/- 0.010). A dendrogram was built with the matrix of isonymy distances, using UPGMA. This method separates the German towns into two main clusters, one in the southern half of the country and the other in the northern half. Within each cluster small subclusters with specific geographic distributions could be delimited. The two main clusters correspond fairly well to the north-south division of German sublanguages (Nieder- and Mitteldeutsch in the north vs. Frankisch-Alemannisch in the south). The other clusters are related to minor sublanguages. Comparisons with the results of a previous analysis of Switzerland's structure are given. From the present analysis isolation by distance emerges clearly, although it is less strong than in Switzerland and indicates that Germany has a fairly homogeneous isonymy structure. The random component of inbreeding estimated from isonymy indicates that eastern Germany is on average more inbred than western Germany.

CD-ROM↗
PubMed1997

Isonymy structure of Sucre and Táchira, two Venezuelan states.

The isonymy structure of two Venezuelan states, Sucre and Táchira, is described using the surnames of the Register of Electors updated in 1991. The frequency distribution of surnames pooled together by sex was obtained for the 57 counties of Sucre and the 52 counties of Táchira, based on total population sizes of 158,705 and 160,690 individuals, respectively. The coefficient of consanguinity resulting from random isonymy (phi ii), Karlin and McGregor's ni (identical to v), and the proportion of the population included in surnames represented only once (estimator A) and in the seven most frequent surnames (estimator B) were calculated for each county. RST, a measure of microdifferentiation, was estimated for each state. The Euclidean distance between pairs of counties within states was calculated together with the corresponding geographic distances. The correlations between their logarithmic transformations were significant in both cases, indicating differentiation of surnames by distance. Dendrograms based on the Euclidean distance matrix were constructed. From them a first approximation of the effect of internal migration within states was obtained. Ninety-six percent of the coefficient of consanguinity resulting from random isonymy is determined by the proportion of the population included in the seven most frequent surnames, whereas between 72% and 88% of Karlin and McGregor's ni for Sucre and Táchira, respectively, is determined by the proportion of population included in surnames represented only once. Surnames with generalized and with focal distribution were identified for both states, to be used as possible indicators of the geographic origin of their carriers. Our results indicate that Táchira's counties, on average, tend to be more isolated than Sucre's counties, as measured by RST, estimator B, and phi ii. Comparisons with the results obtained for other. Venezuelan states and other non-Venezuelan populations are also given.

Emigration and Immigration↗
PubMed1997

[Genetic structure of the population of Guarico, Venezuela, studied through isonymy].

The genetic structure of the State of Guárico, Venezuela, was studied through the distribution of surnames from individuals above 40 years of age, obtained from the register of electors. The sample studied consisted in 109,200 individuals and 14,138 different surnames. For each of the 32 counties of the State, the following estimators were calculated: percentage of the population included in surnames which appear only once (estimator A), percentage of the population included in the seven most frequent surnames (estimator B), the coefficient of consanguinity due to random isonymy (n phi ii), and Karlin and McGregors ni nu, an estimator of migration. The correlation between n phi ii and B was 0.97, indicating that 94% of the variation observed in the coefficient of consanguinity due to random isonymy is due to the seven most frequent surnames. The correlation between A and ni was 0.93, so that 86% of the variation observed in ni, is due to surnames which appear only once. On the other hand, correlations between A and B, and between n phi ii and nu were non significant (0.25 and 0.01 respectively), meaning that they are measuring different features of population structure: B and n phi ii, and v were non significant (0.25 and 0.01 respectively), meaning that they are measuring different features of population structure: B and n phi ii, isolation, and A and nu, migration. The most isolated counties of Guárico, according to n phi ii and B, are Santa Rita, Espino, El Calvario, Ortiz and Santa María de Ipire. Microdifferentiation of the State was studied through the estimation of RST, which gave a value of 0.0008. Comparing this value with those obtained in other Venezuelan States, it is found that Guárico, with Aragua and Yaracuy, are among the least differentiated States, probably because of the absence of important geographical barriers and the nearness to the Capital City of our country.

Adult↗
PubMed1995

Phylogeny inferred from codon usage pattern in 31 organisms.

We employed the Codonusage database to analyze the codon usage pattern in 31 organisms from all the main biological taxa. We tested the similarity in codon usage pattern between each organism and all the others by the Pearson linear correlation coefficient. The 465 values obtained were located in a 31 x 31 triangular matrix from which a correlation distance matrix was calculated. An evolutionary dendrogram was then constructed from these distances. The results showed a fair correlation between codon usage patterns and phylogenetic relationships, at least for organisms which diverged in rather recent times (end of Jurassic--beginning of Cretaceous).

Animals↗
PubMed1995

The usage of oligopeptides in proteins correlates negatively with molecular weight.

We scanned the Swissprot databank to study the distribution of oligopeptides in sequenced proteins. We observed that in 7839,000 amino acids in the bank, the frequency is strongly and negatively correlated with molecular weight. The correlation coefficient is -0.63 for single amino acids, -0.58 for dipeptides, -0.54 for tri- and -0.46 for tetrapeptides. In subsets of proteins of man, mouse, rat drosophila, yeast and E. coli, the correlations were very similar to those for the total database. The intensity of the correlation diminishes linearly with the length of the peptide. We attributed the loss of dominance of molecular weight in determining the frequency of oligopeptides of higher order, to the emergence of function in longer oligopeptides. In the case of dipeptides, we observed that those composed of the same amino acid are in great excess in comparison with their expectation. The WW dipeptide is singular, in the sense that is observed/expected ratio is 13.5 standard deviations above the average ratio.

Amino Acids↗
PubMed1994

Possible identity of transcription and translation signals in early vital systems.

The distribution of codons was analysed in three classes of eukaryote proteins having widely different evolutionary rates: 78 histones, 40 tubulins, and seven fibrinogens. In this set of genes, (i) it was confirmed that codons which are components of known transcription signals, like ATA, are used infrequently when a synonym is available, particularly in the more constrained proteins, and (ii) it was observed that the three codons which have an iso-accepting transfer with anticodon UAA, UAG or UGA are also suppressed. Then, the distribution of UAA, UAG and UGA trimers was studied in 498 tDNAs and 198 rDNAs. It was found that these trimers are weakly but significantly suppressed in tDNAs and to a lesser extent in rDNAs. It was advanced that the present suppression of ATA, which codes for Methionine in several mitochondria, and of the TAA, TAG and TGA trimers in tDNAs, might be an indication that at the very early stages of the evolution of translation and transcription the signals for initiation and termination were shared by the two processes.

Amino Acid Sequence↗
PubMed1994

Codon usage and evolutionary rates of proteins.

The 61 codons and the three terminators were counted in the coding sequences of 31 families of proteins of higher vertebrates. The protein families were ordered according to their evolutionary rate. In each family, the ratio between the Observed and Expected frequency of each codon was obtained (O/E ratio). A strong and significant positive correlation was observed between the O/E ratio of the eight codons AAC, TAT, ATA, GAA, ACA, AAT, ATG and CGA and the evolutionary rate of the protein. A negative and significant correlation was observed for codons AAG and GAG. It was advanced that the functional constraints of proteins can influence the usage of codons, particularly for those trimers which are components of signal sequences. It was also observed that the O/E ratios of the terminators are negatively correlated with the evolutionary rate of the protein they terminate, and the correlation is significant for TAA and TGA, which in vertebrates might be older than TAG.

Animals↗
PubMed1994

In vivo genotoxic interactions among three phenolic benzene metabolites.

Three benzene metabolites, hydroquinone (HQ), cathecol (CAT) and phenol (PHE) were studied to define their possible interaction in inducing micronuclei (Mn) in mouse bone marrow polychromatic erythrocytes (PCEs). HQ and CAT, administered separately, induced Mn while PHE showed no genotoxic effects. Binary and ternary mixtures of two or three metabolites gave different results, causing considerable increase or decrease in Mn induction. HQ and PHE, in binary mixtures, as well as PHE and CAT, increased Mn synergistically, while HQ and CAT interacted negatively. The genotoxicity of ternary mixtures was mainly the consequence of two metabolites: HQ and CAT. The maximal effect obtained is far below the induction of Mn consequent to benzene treatment. These data suggest that toxic and genotoxic effects of benzene alone could be the result of more complex interactions among these and other metabolites.

Animals↗