Y Haplogroup I
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Semino et al believe that haplogroup "I" stems from a group (Gravettian culture) that arrived in Europe from the Middle East about 20,000-25,000 years ago. The Gravettian culture was "known for its Venus figurines, shell jewellery, and for using mammoth bones to build homes". The mutation that defines haplogroup I (M170) is believed to have occurred in Europe, so haplogroup I is found only on that continent (other than recent admixture). For some reason there has been very little published concerning the details of the structure and distribution of haplogroup I. The data in Cinnioglu's paper is some of the first detailed information that has become available on haplogroup I and it's sub-groups. Unfortunately most of these I sub-groups had too small of a sampling in Cinnioglu's study to create meaningful allele frequency graphs. But since this is the first time that information about these sub-groups has been available I've included them anyway.
I1a:
While there is too little data to draw any firm conclusions, it appears that YCC haplogroup I1a is the best candidate for the identity of the members of HG2 in Iceland as reported in Helgason's study of Y chromosomes in Iceland. A comparison of the I1a vs HG2 allele frequency graphs is shown here. There appear to be five I1a haplotypes among the 30 most common haplotypes in the YSTR.org database. Those haplotypes can be seen here. The HG2 haplotype shown on the main page is probably close to the 25 marker modal haplotype for I1a.
I1b:
The modal alleles for I1b in the graphs below match up well with the "Dinaric Modal Haplotype" described by Barac et al in their study of Croatian Y Chromosomes. Barac et al believe that this group may have spent the Last Glacial Maximum in a Balkan refugium. This group is numerous enough to appear among the 30 most common haplotypes in the YSTR.org database. That haplotype can be seen here.
Cinnioglu's study found no Turkish men who belonged to the sub-group of I1b known as I1b2. I1b2 is usually seen among populations that are descended from Europe's Paleolithic population - though it seems to have originated on the island of Sardinia. According to Zei et al I1b2's modal haplotype is characterized by the unusual alleles of YCAII=11,21. Bosch's 2001 study showed that I1b2 may also be characterized by large values of DYS19 (16 or 17). More information about I1b2 can be found here.
I1c:
Cinnioglu's study included a sub-group of I (called I1c) that was not included in the 2002 version of the YCC Y chromosome tree. It is defined by the SNP marker M223. Passarino et al mention in their paper on Norwegian Y chromosomes and mtDNA that M223 had previously been seen in 2 out of the 6 German samples analyzed in Semino's study, and that one was seen among the 74 Norwegian males they studied. Their 2002 paper states that the frequency of I1c "elsewhere in Europe remains unknown".
The distribution of YCC haplogroup I in Europe can be seen as the group colored in light blue on the map on the second page of Semino's paper on European Y chromosomes.
[IMG]
http://freepages.genealogy.rootsweb.com/~dgarvey/DNA/RelGen/Underhill_2003_I.jpg[/IMG]
http://freepages.genealogy.rootsweb....ll_2003_I.html
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