Pages

Wednesday, November 18, 2015

The Inca Child from Argentina and a new haplogroup C1bi


The third and last post of the day deals with a novel mtDNA sub clade found in the mummified (due to the high dry altitude of the Andes) remains of a child sacrificed by the Inca people about 500 years ago. The child's mtDNA is similar to that found in some very old remains in Upward Sun River, Alaska.


The paper (see below [1]), reports that this new variety of C1b haplogroup and that it is very ancient: The authors believe it originated some 14,000 years ago along the Andes in South America. As it is rare nowadays they suggest that either (a) it is due to a bias in sampling -so it has not been detected in large frequencies, or (b) it has become extinct in many parts due to the mass deaths caused by the turmoil of European discovery and conquest during th 1500s. They write:


" the phylogenetic patterns of C1bi point to a geographic origin in the Andean side of the South American sub-continent approximately 14 kya. The haplotype found in the Inca child from the Cerro Aconcagua, interpreted in the light of present-day variation in South America and together with the different archaeological and anthropological findings, supports the existence of demographic movements along the Pacific coastline during the Inca period. The fact that C1bi is very uncommon in present-day populations from South America could be explained by insufficient sampling of modern populations (although the present-day haplotype databases of mitogenomes and partial mtDNA sequences are very large). Alternatively, this rarity could reflect important changes in the gene pool of South America since the period of the Inca civilization. Further research on modern and ancient South American populations" [1]


Regarding the age, those 14 kya are maybe even too recent, their confidence intervals are rather wide, from 5 to 23.6 kya. The child was sacrificed 500 years ago during an Inca rite on the highest mountain located outside of Asia, the Aconcagua.


They point out that " C1b most likely arose relatively early, either in Beringia or at a very initial stage of the Paleoindian southward migration [...] While some C1b sub-clades were exclusively observed in Mesoamerica or in South America, a few of them were found in both territories." The map published in the paper shows the distribution of C1b across America: it is strongly concentrated in Mexico, Peru and strangely, in Puerto Rico.


C1b haplogroup map in America
C1b distribution heat map. From [1]

The child has a new clade named C1bi (where "i" stands for "Inca") and is similar to the clade "C1b13. The TMRCA of this sub-clade is 11.8 (8.6–15.1) kya; it is virtually absent from North-Central America and its geographic location is mainly centered in Chile", which fits in the same geograpic area of C1bi.


The clade is very rare: "By querying large databases of control region haplotypes (>150,000), we found only a few C1bi members in Peru and Bolivia (e.g. Aymaras), including one haplotype retrieved from ancient DNA of an individual belonging to the Wari Empire (Peruvian Andes)." [1]


I have already written about the loss of diversity in America not because of a Beringinan or Out of Asia bottleneck but due to the high death toll that virtually wiped out the Native Americans when they were contacted by the European navigators after 1492. Interestingly, my post cites a paper which points out that Hg C suffered a greater impact of lost diversity (with Hg D) than either haplogroups A or B.


In another post I tried to link mtDNA hg. C1 with the Neanderthals. In this post I mention that hg C1 spans Eurasia and America, closely following the Neanderthal homeland.


In [1], the authors found one sample "...that belongs to haplogroup C1b13b sampled in a Spanish individual, although born in Talagante (Chile); therefore we labeled it here as originating in America" [1], in other words a person of European origin born in America carried a European variant of C1. They assumed perhaps that this individual had some Amerindian admixture, I believe that it is just a coincidence that this man has C1 and by chance his ancestors migrated to America.


The hot spot in Puerto Rico is very interesting and requires some explanation. The local Carib - Taino natives were wiped out early during the discovery period. So where did the C1b found there come from?


Sources
[1] The complete mitogenome of a 500-year-old Inca child mummy Alberto Gomez-Carballa, Laura Catelli, Jacobo Pardo-Seco, Federico Martinon-Torres, Lutz Roewer, Carlos Vullo y Antonio Salas Scientific Reports 5, Article number: 16462 (2015). Nature, Nov. 12, 2015 doi:10.1038/srep16462


Patagonian Monsters - Cryptozoology, Myths & legends in Patagonia Copyright 2009-2015 by Austin Whittall © 

3 comments:

  1. Austin,
    Dillehay et al, have just published a paper detailing a human presence at Monte Verde 18kya, and they allude to a vey ancient back migration of S americans in N America.
    It would help explain how downstream C haplo groups are showing up in early N American remains.
    http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0141923

    John Hawks has a very good write up on it

    ReplyDelete
  2. Ron,
    Thank you for sharing the link to Dillehay et al.'s paper it is extremely interesting. It also hints at an earlier date than the 18 kya mentioned in the paper.
    The paragraph where they state that:
    "A dubious association of one percussion flake of basalt, another flake, and a non-feature scatter of charcoal was recorded at a deeper level (1.47–1.49 m) in a downslope extension of Unit 56, which was sealed by overlying strata MV-1 to MV-4 (see Fig 5 and Text B in S1 File). The charcoal dated between ~23,515 and 22,100 cal BP. In addition, a white quartz chopper, two spherical stones, and an unknapped flake were recovered in Unit 55, the upper lower level of stratum MV-7, site MV-1 (Text A in S1 File, see S6 and S7i Figs). These lithics were not associated with a feature and datable material. Previously, peat balls at the 1.63 and 1.69 m in the upper lower levels in MV-I were 14C dated between ~23,000 and 29,000 BP (see Table 1). The middle lower to basal levels of stratum MV-7 are dated ~33,000 BP by 14C dates on wood charcoal associated with burned features and greater than 40,000 years ago by OSL assays (see Text G in S1 File) [13,14]. A fragment of animal skin in a peat ball at the 2.03 m basal level in Unit 57 of the MV-I site recently 14C dated at 43,500 BP. This date generally agrees with a measure of 42,100 BP on a previously 14C assayed peat ball at the 1.97 m non-cultural basal level in Test Pit 42 of MV-1 [14]. The data from these deeper levels are still too meager and inconclusive to determine whether they represent human activity or indeterminate natural features. At present, the latter case is perhaps more feasible, given that there is presently no convincing archaeological or other data to substantiate a human presence in South America prior to 20,000 years ago."

    Is very interesting indeed. Perhaps they are constrained by the lack of consensus to accept an older date for the peopling of America, but the evidence is there, maybe 25 to 40 kya.

    ReplyDelete
  3. I recently found out that I am related to mamma Juanita, another incan mummy with the same genotype as this little boy. The geneticists said it was 95% accurate.The crazy thing is that I'm also Italian, British, French, Slavic, German, Mexican, Columbian, and Peruvian? Very interesting to see how the timeline of my lineage correlates with world history and such but so much is still a mystery?

    ReplyDelete