%0 Journal Article %T Population-genetic comparison of the Sorbian isolate population in Germany with the German KORA population using genome-wide SNP arrays %A Arnd Gross %A Anke T£¿njes %A Peter Kovacs %A Krishna R Veeramah %A Peter Ahnert %A Nab R Roshyara %A Christian Gieger %A Ina-Maria Rueckert %A Markus Loeffler %A Mark Stoneking %A Heinz-Erich Wichmann %A John Novembre %A Michael Stumvoll %A Markus Scholz %J BMC Genetics %D 2011 %I BioMed Central %R 10.1186/1471-2156-12-67 %X The degree of relatedness was significantly higher in the Sorbs. Principal components analysis revealed a west to east clustering of KORA individuals born in Germany, KORA individuals born in Poland or Czech Republic, Half-Sorbs (less than four Sorbian grandparents) and Full-Sorbs. The Sorbs cluster is nearest to the cluster of KORA individuals born in Poland. The number of rare SNPs is significantly higher in the Sorbs sample. FST between KORA and Sorbs is an order of magnitude higher than between different regions in Germany. Compared to the other populations, Sorbs show a higher proportion of individuals with runs of homozygosity between 2.5 Mb and 5 Mb. Linkage disequilibrium (LD) at longer range is also slightly increased but this has no effect on the power of association studies.Oversampling of families in the Sorbs sample causes detectable bias regarding higher FST values and higher LD but the effect is an order of magnitude smaller than the observed differences between KORA and Sorbs. Relatedness in the Sorbs also influenced the power of uncorrected association analyses.Sorbs show signs of genetic isolation which cannot be explained by over-sampling of relatives, but the effects are moderate in size. The Slavonic origin of the Sorbs is still genetically detectable.Regarding LD structure, a clear advantage for genome-wide association studies cannot be deduced. The significant amount of cryptic relatedness in the Sorbs sample results in inflated variances of Beta-estimators which should be considered in genetic association analyses.The Sorbs living in the Upper Lusatia region of Eastern Saxony are one of the few historic ethnic minorities in Germany. They are of Slavonic origin speaking a west Slavic language (Sorbian), and it is assumed that they have lived in ethnic isolation among the German majority during the past 1100 years [1]. Therefore, this population may be of special interest for genetic studies of complex traits.The value of isolated populations f %U http://www.biomedcentral.com/1471-2156/12/67