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General Forums - Note: You must Be Logged In to post. Anyone can browse. => Autosomal Block DNA Testing - "Family Finder" and "Relative Finder" => Topic started by: rms2 on April 05, 2012, 07:19:48 AM

Title: New Paper: "Cryptic Distant Relatives"
Post by: rms2 on April 05, 2012, 07:19:48 AM
Here ( it is.

Quote from: Abstract

Although a few hundred single nucleotide polymorphisms (SNPs) suffice to infer close familial relationships, high density genome-wide SNP data make possible the inference of more distant relationships such as 2nd to 9th cousinships. In order to characterize the relationship between genetic similarity and degree of kinship given a timeframe of 100–300 years, we analyzed the sharing of DNA inferred to be identical by descent (IBD) in a subset of individuals from the 23andMe customer database (n = 22,757) and from the Human Genome Diversity Panel (HGDP-CEPH, n = 952). With data from 121 populations, we show that the average amount of DNA shared IBD in most ethnolinguistically-defined populations, for example Native American groups, Finns and Ashkenazi Jews, differs from continentally-defined populations by several orders of magnitude. Via extensive pedigree-based simulations, we determined bounds for predicted degrees of relationship given the amount of genomic IBD sharing in both endogamous and ‘unrelated’ population samples. Using these bounds as a guide, we detected tens of thousands of 2nd to 9th degree cousin pairs within a heterogenous set of 5,000 Europeans. The ubiquity of distant relatives, detected via IBD segments, in both ethnolinguistic populations and in large ‘unrelated’ populations samples has important implications for genetic genealogy, forensics and genotype/phenotype mapping studies.

Title: Re: New Paper: "Cryptic Distant Relatives"
Post by: Jim Rohrer on April 09, 2012, 03:47:34 PM
You wrote that your findings have important implications.  Are we to infer from all these distant cousins that narrowly defined European "populations" are perhaps slicing the data too finely?  The original "peoples of Europe", pre-dna, were slavic, germanic, italian, spanish, ukrainian, british, french and polish.  Or if you go with linguistic groups, there are slavic, latin, germanic, celtic, indo-iranian, greek, albanian and baltic ( 

Should we focus less on haplogroups and more on larger groups?

Title: Re: New Paper: "Cryptic Distant Relatives"
Post by: Jim Rohrer on April 10, 2012, 02:37:05 PM
Here are some web hits on r1b1a2 that make me scratch my head.

R1b1a2 Half of European Men Share King Tut's DNA - Skadi Forum › ... › General Bio-Anthropology
Aug 23, 2011 – By Alice Baghdjian LONDON Aug 1 (Reuters Life!) - Up to 70 percent of British men and half of all Western European men are related to the ...

King Tut is of Haplogroup R1b1a2 (Celtic)