Samo bih savetovao maksimalan oprez oko proračuna starosti.
Tu ne samo da se luta, već se proscene razlikuju i za 300%; pa i više.
Ipak, nadjoh nešto, pa da postavim.
Evo jedan kvalitatan sajt koji se bavi J2 HG.
http://j2-ydnaproject.org/analysisphase3.html
"J2b-β (J2b-Beta) appears to be equivalent to J2b M102/M205+ J2b1 - Karafet et al. 2008 ).
These are preliminary findings only, - more extended M205+ haplotypes need to be known before we can make any scientifically firm/objective conclusions.
Within the project there are 6 haplotypes in J2b-alpha, four of which are SNP confirmed as M205+ (the remaining two are not yet SNP tested). The markers that most reliably predict a haplotype is J2b-β are found in the second FTDNA results panel, - so at least 25 markers are needed to reliably identify this cluster.
As yet there is no data on M205+ in published DNA studies, so its distribution and the potential age of the cluster has not yet been calculated in Academic research.
The geographical origins of the 6 members in J2b-alpha are: Serbia, Mexico, Greece (2 haplotypes), Germany, and England. Of note is the fact that there are genetic distances of 14-23 at 37 markers, which implies that the clade may have been founded at
least 4000 years ago (assuming an average mutation rate of .002, and an average generation time of 27 years)."
DA nije sve tako jednostavno govori i ovaj komentar.
"Paradox - greater microsatellite variation in Indian J2b, but greater phylogenetic variation in European J2b.
One question that could be asked is - Is the J2b in India derived from the J2b in Europe, or vice versa? We would hypothesize that it is derived from neither, and both are derived from an as yet unidentified source population. We can also hypothesize that after moving from the original source population, both separate populations of J2b have experienced different demographic factors which have resulted in different impacts on the microsatellite and phylogenetic variation. This hypothesis is the best explanation for the apparent paradox of greater microsatellite variation in Indian J2b, yet greater phylogenetic variation in European J2b. Our rationale for this is as below:
Assuming that the coalescence dates determined by all researchers have been calculated in a consistent unbiased manner between haplogroups, we could easily conclude that J2b in Europe is derived from the J2b in India. On the other hand, according to Sengupta et al. 2006, all of the J2b in India is M241+, whereas Europe has both J2b M241+ and J2b M241- (as well as J2b M205+). We would therefore expect greater variation in Europe (since there is greater phylogenetic diversity).
We can also conclude that the J2b in India is not derived from the J2b in Europe. This can be deduced from the greater coalescence date for J2b in India, and also the fact that E3b is either absent or negligible in populations within India.
Therefore, the J2b in India is from a source population that pre-dates the Bronze age expansion of J2b and E3b in the Balkans.
The disparity may be due to different demographic events leading to reduced variation in Europe (eg. loss of a greater percentage of lineages due to more daughtering out, bottlenecks etc).
In simple terms - Perhaps many of the branches of J2b in Europe were pruned out. Therefore we hypothesise that the J2b in both Europe and India are derived from an as yet unidentified common source, with more of the original J2b M241+ microsatellite (ie. STR) variation preserved in India compared to Europe, due to differing demographic effects.
Another factor to consider is that there are distinct differences in the DYS 461 values between European M241+ and Indian M241+. Most European M241+ haplotypes have DYS 461 values of 10, and most Indian M241+ haplotypes have DYS 461 values of 9. We cannot as yet determine which marker value is likely to have been the ancestral marker value. It would be interesting to know what marker values M205+ haplotypes have (as yet, none of the projects M205+ haplotypes have been tested for DYS 461).
We should also consider the fact that it may be false logic to conclude that the calculated coalescence age for J2b in India is accurate even if the European and Indian coalescence ages for R1a are more-or-less equivalent. Zhivotovsky et al. 2006 states that the demographic factors that cause disparities between the mutation rate inferred from population data, and the mutation rate inferred from father-son studies will differ between different haplogroups, and different populations. The calculation method used by Zhivotovsky et al. (2004) was derived from studies examining microsatellite variation in populations with known foundation times (Bulgarian Gypsies, and New Zealand Māori). There will be some populations that experienced greater bottlenecks than these populations (thus the Zhivotovsky et al. (2004) method will underestimate coalescence age), and there will be populations that experienced fewer bottlenecks than these populations (thus the Zhivotovsky et al. (2004) method will over estimate coalescence age).
The project is currently working on formulating further hypotheses regarding the demographic history of J2b. We are however aware of the fact that it is very difficult to conclusively attribute any haplogroup to any specific historical groups/ population movements. We will therefore refrain from hypothesizing that any specific historical/archeological groups were responsible for the demographic expansion of J2b (regardless of how tempting it might be to attribute J2b to groups such as Indo-Europeans)."
Pogledajte prilog 321376
"J2b M205+ (represented by J2b-Beta cluster) is a clade for which very little is known. Virtually all of our knowledge of this clade is derived from what we have learned within this project. The map depicts what distributions are known (not shown is one haplotype from Mexico, and one haplotype from Russia which is suspected to be M205+). The greatest number in the project are from Greece, and the most divergent haplotype is from Serbia. This might suggest an origin from the Balkans (which perhaps isn't particularly illuminating, since the Balkans seems to be the region from which J2b as a whole is most frequent). It is perhaps relevant to again note the fact that Pericic et al. 2005 found approximately 50% of J2b in the Balkans to be M241-, with the greatest frequency of J2b M241- to be in Serbia. Unfortunately we cannot be sure what proportion of those J2b M241- might have been J2b M205+, since M205 was not tested. We can only speculate that perhaps a large proportion of those tested as M241- were M205+.
J2b-Beta cannot be conclusively identified at 12 markers (although haplotypes do have a tendency of having higher than normal DYS 385 values), and is identifiable by its values at DYS 454 and DYS 437. At the time of the February 2007 cluster analysis there were insufficient numbers of J2b-Beta with 37 markers to produce modals for the 26-37 marker panel. Modals for this panel have now been added (none of the markers in this panel appear to be significantly diagnostic). At present only one J2b-Beta haplotype has been tested at 67 markers."
J2b M205 је prisutan i na Siciliji, a ima ga i na severu.
http://www.familytreedna.com/public/J2-M172/default.aspx?section=ymap
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lep primer gde se vidi koliko je demokratija pogubna.
