December 05, 2004

Abstracts of Y-user workshop papers

Some interesting tidbits from a collection of interesting abstracts of papers and posters presented at a recently held International Forensic Y–User Workshop (pdf)):

Evaluation of the Ethnic Composition in the Population of Argentine

D Corach et al.

"As depicted in most Latin American countries, there is in Argentina, a clear asymmetry regarding Amerindian matrilineage mestizo (83.3%) when compared with Amerindian patrilineage (16.7%). A clear discrepancy arose in comparison with the
physical anthropological position that claims a minimal aboriginal component in Argentina’s population. This contribution provides additional information that supports a more relevant Amerindian component in a country that claimed to be the most European one of the entire Latin America."

Y-chromosome SNP and STR analysis in a Belgian population sample

R Decorte et al.

"The developed approach has been applied to a Belgian population sample of 98 males
that has been previously typed with the Powerplex Y System (Promega). In total, 6 haplogroups (E3b, G, I, J2, R1a1 and R1b) were observed in more than one individual while 2 haplogroups (A and F*(xG,H,I,J,K) or J*) were each present in a single individual. The two most common haplogroups were R1b (60.6%) and I (13.1%) which is similar to other studies of West-European populations."

Y-STR haplotypes from East Germany – differences between carriers of surnames of Germanic and Slavic origin?

UD Immel et al.

"The goal of the present study was to investigate whether Y-chromosome haplotype analysis is capable to distinguish groups with surnames of different origin. To this end, DNA samples were obtained from 400 males born in the south of Saxony-Anhalt. Samples were divided into three groups namely those with a Germanic surname, those with a Slavic surname and those with mixed origin of the surnames. The minimal Y-STR haplotype of these two groups was analysed by AMOVA. A highly significant difference (p < 0.001,FST = 0.0309) between the Germanic and the Slavic groups was observed. When comparing this to other populations using published data, this difference is similar to that between European populations of large geographical and linguistical
differences (like e.g. between Cologne and Budapest). On the other hand, the group with surnames of the mixed origin were indistinguishable from the Germanic group (FST = 0.0008). Our results reflect that the Y chromosomal lineages of Germans born in southern Saxony-Anhalt differ depending on the ethnic and linguistic origin of their surname."

Genetic differentiation follows political borders in Europe: Y-chromosome variation in Poland and Germany

M Kayser et al.

"To test for human population substructure within Europe we have investigated Y chromosome diversity using seven microsatellites and ten binary markers in samples from eight regionally distributed populations from Poland (n = 913) and eleven from Germany (n = 1215). Based on both marker systems we observed statistically significant genetic differentiation between all Polish and all German regional populations but also genetic homogeneity within each of the two neighboring geographic regions. We suggest that this scenario can be best explained by very recent events in human population history, namely the politically forced human resettlements during and after World War II, rather than more historical population movements. In addition, our findings have important consequences for the use of Y chromosome markers in forensics and strongly argue in favor of regional Y chromosome databases and / or the implementation of population substructure into more global Y chromosome databases."

Y-chromosomal DNA variation in East Asia

Y Xue et al.

"East Asia has been inhabited by modern humans for > 50,000 years and now holds more than one quarter of the world population. Genetic analysis using classical markers identified a major north-south distinction (Cavalli- Sforza et al. 1994), which may reflect separate origins of northern and southern populations from different migrations out of Africa. The Y chromosome provides high-resolution male haplotypes and thus an opportunity to investigate male-specific history. We have typed 1012 individuals from 28 populations in China, Mongolia, Korea and Japan with 45 binary markers (mostly SNPs) and 16 microsatellites from the Y chromosome. SAMOVA analysis of Y-SNPs was used to identify the geographical divisions that apportion the maximum amount of genetic variation between groups (Dupanloup et al. 2002). It did not show the traditional north-south division, but identified small groups of distinct populations, mainly in the south. Why should Y-chromosomal variation show a different structure from that of the rest of the genome? We have investigated the distribution and time- depth of individual haplogroups. For example, haplogroup O is
largely confined to East Asia and one of its subdivisions, O3, is widespread and common in China. A subset of these chromosomes, O3/-d, is concentrated in southern China, particularly in the two Yao populations which formed one of the major SAMOVA divisions. The time depth of the O3/-d lineage was estimated at approximately 5,900 (4,500 - 8,200) years from its microsatellite variation using the program BATWING
(Wilson and Balding 1998), so must have spread after this date. A second common haplogroup is C, and C3c chromosomes are concentrated in northeastern China where they are present at highest frequency in the Oroqen population, another of the major SAMOVA divisions. A substantial subset of them appear to have expanded very recently, < 900 years ago. These results suggest that East Asian Y-chromosomal variation has been substantially reshaped by recent events within Neolithic and historical times."

Y-STR differentiation and substructuring in Pyrenean populations.

E Arroyo-Pardo et al.

"The Pyrenees are a mountain range which spans 430 km from the Atlantic to the Mediterranean shore. Its widest section (160 km) lies in the central part and contains also the highest peaks, most over 3,000 meters. Though the Pyrenees have been populated since Paleolithic times, they present a very difficult geography
that produces some degree of isolation of populations. Due to this orography, Pyrenees were perhaps a marginal area for the advance of the farming wave during Neolithic (Arias Cabal, 1991) and could be less affected by the farming spred than the rest of the Iberian Peninsula. We studied the 9 loci comprised within the minimal haplotype of the Y-STR Haplotype Reference Database (www.yhrd.org) in the autochtonous populations from East Pyrenees – Cerdanya (n = 42) and Urgell (n=34) – Central Pyrenees – Aran (n=30) –, andWest-Pyrenees – Jacetania (n=28) and Lesaca (n=42). Nine other Iberian populations from Spain and Portugal were used for comparison. Two Basque samples were also introduced in order to comprise the Basque- speaking region within the study. Genetic diversity parameters, AMOVA and mismatch distributions reveal substructuring of Pyrenean populations according to a East-West gradient. Results also point out a certain degree of differentiation between Pyreneans and the rest of Iberian samples. The genetic landscape produced may well support the isolation of the Pyrenean populations during the Neolithic diffusion due to the geography of the region."

A study on Y-STR haplotypes in the Saxon population from Transylvania – is there evidence for a German origin?

L Barbarii et al.

"Y chromosome markers are increasingly used to investigate human population histories, being considered to be sensitive systems for detecting the population movements. In this study we present Y-STR data for Transylvanian Saxons in comparison with Y-haplotypes from Romanians and other European populations.
The Transylvanian Saxons, called like that since medieval times, are representing a Romanian minority population with assumed German origin. They have settled in the Arch of Romanian Carpathian Mountains in the earliest of the 12th century. Historical and dialectal studies strongly suggest that they do not originate from Saxony, but more probably from the Mosel riversides (Rhine affluent) and also from the Eifel Mountains Valley (present territory of Luxembourg). Living protected by fortified cities in compact communities, they still represent a quite distinct population in Transylvania. Males selected for this study had all Saxon surnames and were classified by the birthplace of the paternal grandfather. The typing results
reflect high Saxon population haplotype diversity. Furthermore, we present data on the haplotype sharing of the Saxon population with other European populations, especially with Germans as well as with Romanians and Transylvanian Hungarians."

Phylogenetic studies of Swedish males by Pyrosequencing of Y-chromosome SNP markers

A Karlsson et al.

"Analysis of Y-chromosomal biallelic markers has become important because of their usefulness in forensics and archaeology. Therefore we have, together with our previous study, designed and established a Pyrosequencing (Biotage, Sweden) methodology for studying 17 biallelic Y-chromosome markers (SRY1532, YAP, SRY4064, M35, M78, M89, M201, M170, M26, M223, M253, 12f2, M9, Tat, 92R7, M17 and M269).
PCR was designed to produce amplicons around 100 bp, suitable for analysis of highly degraded DNA. We also present a population study on 305 Swedish males living in seven different regions. Genomic DNA from the males was typed for the 17 markers mentioned above. The population could thus be divided into 16 different haplogroups. Together with results from minimal haplotype Y-STR-analysis population parameters
will be calculated, for example FST statistics, diversities and others. According to preliminary data, Västerbotten significantly differs from other regions which is also shown by Roewer et al (Hum Genet in press)."

Y-chromosomal STR haplotypes in Sicily

C Robino et al.

"The reconstruction of the genetic history of Sicily is extremely difficult, because of the complexity of human movements and settlements that interested this area of the Mediterranean Sea in prehistorical and historical times. Previous studies, based on classical and DNA markers (autosomal STRs and mtDNA), are discordant regarding the presence of genetic heterogeneity within the island, some of them suggesting a geographical pattern of differentiation following a longitudinal (East- West) axis. Analysis of Y-chromosome biallelic polymorphisms showed a haplogroup frequency distribution similar to Southern Italy and Greece. In this study, Y-STRs currently used to define the minimal haplotype employed in the “Y-STR haplotype reference
database” (DYS19, DYS389I-II, DYS390, DYS391, DYS392, DYS393, and DYS385) were typed in 215 unrelated males from Sicily. Individuals represented in the population sample were chosen from both geographically and historically distinct areas of the island: Trapani, Santa Ninfa, Alcamo (Western Sicily); Sciacca, Caccamo, Mazzara del Vallo (Central Sicily); Troina, Ragusa, Piazza Armerina (Eastern Sicily). Comparison of haplotype distributions was carried out between different sampling regions and with neighbouring Mediterranean populations."

Y-chromosomal STR haplotypes in Macedonian population samples

M Spiroski et al.

"Eleven Y-chromosomal short tandem repeats (STRs), DYS19, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS385, DYS437, DYS438, DYS439 were typed in DNA samples from Macedonian population (n = 150). The Macedonian population sample has two dominant minimal haplotypes with frequencies > 5% (13,13,30,24,10,11,13,16-18 and 16,13,31,24,11,11,13,14-15). By haplotype extension (DYS437, DYS438, DYS439) both of these minimal haplotypes can be further split up into 4 different, 1-allele step deviant chromosomes, respectively. The frequencies of the 20 most frequent minimal haplotypes in the Macedonian population have been compared with those from populations inhabiting 4 neighbouring geographic regions sampled for the YHRD, i.e. Albania (n = 101), Bulgaria (n = 122), Croatia (n = 150) and Greece (n = 101). The analysis revealed the most pronounced similarities in the minimal haplotype frequency with the Croatian and Albanian samples. The gene diversity for the minimal haplotype was 0.9838, for the 11-locus haplotype 0.9889. One haplotype analysed in this study includes a duplication of the locus DYS19 (alleles 15,16), a type of mutation which has been observed so far with a frequency of about 0.05% in 21,546 individuals in the YHRD (release 10 from February 26, 2004)."

Genetic diversity of three Singapore populations using Y-Short Tandem Repeat and mitochondrial D-loop loci

RYY Yong et al.

"Genetic distances comparison between populations using both Y-STR and mtDNA markers indicated Chinese-Malay are the most related, while Chinese-Indian are the furthest apart genetically. To our knowledge, this study represents the most comprehensive report of Y-STR and mtDNA haplotype distribution in Singapore to date."

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