Tracing my paternal ancestors through Y DNA

The human Y chromosome is a male-specific sex chromosome. When mutations (errors in the copying process) arise in the Y chromosome, they are passed down directly from father to son in a direct male line of descent and define a tree of Y “haplogroups”. The mutations on the Y chromosome can thus be used to trace our paternal ancestors all the way back to the most recent common paternal ancestor of all men alive today, Y chromosomal Adam.

When I first got interested in genetic genealogy around 2010, I had my DNA tested by the National Genographic Project, funded by the National Geographic to collect over a million DNA samples to map the patterns of human migration across the world. This project measured mutations known as short tandem repeats (STRs) at 12 sites, and gave a statistical prediction of my Y-haplogroup, R1b (M343) and subclade R-M269. A year later I upgraded my Y-DNA analysis to 44 STRs with Ancestry.com. At the time, I decided that I would wait for the technology to improve and the cost to drop and do a more comprehensive test which would definitively determine my Y haplogroup.

And so last year I did the Big Y-700 test with FamilyTreeDNA which examines 700 short tandem repeats, and over 200,000 single-nucleotide polymorphisms(SNPs) identifying known haplogroups as well as millions of locations where there may be new branch markers on the Y chromosome. This company claims to have the world’s largest genealogical YDNA database with over 2 million people included.

A single-nucleotide polymorphism (SNP, pronounced snip) is a DNA sequence variation occurring when a single nucleotide adenine (A), thymine (T), cytosine (C), or guanine (G) in the genome differs between individuals. For example, two sequenced DNA fragments from different individuals, AAGCCTA to AAGCTTA, contain a difference in a single nucleotide. In this case we say that there are two alleles: C and T. Almost all common SNPs have only two alleles.

Although it contains ~1% of the genome length in a human male cell, the lack of recombination along most of the Y chromosome makes it relatively easy to construct the evolutionary relationships among the Y haplogroups, known as a phylogenetic tree. The most recent version of the Y chromosome phylogenetic tree is maintained by the International Society of Genetic Genealogy (https://isogg.org/tree/index.html). The human Y chromosome contains about 56 million positions or base pairs. Of them, roughly 23 million base pairs (40%) are useful for phylogenetic analysis and FamilyTree DNA has identified over 500,000 unique mutations in the Y chromosomes of their testers.

Figure 1. Migration routes of Y haplogroups dating back to Y-DNA Adam (denoted by capital Y) in West Africa around 275,000 years ago. All humans originated in Africa and migrated out, branching into the main out of Africa haplogroups, including haplogroup R predominant in Western Europe. Details of Eurasian haplogroup locations and migrations have changed somewhat from those shown on this 2010 map from Wikimedia. (Source: Chakazul Wikimedia Commons 18 Sep 2013)

The Y chromosome has regions of fast mutating STRs and stable regions with for which bias-free estimates of SNP mutations rates have been obtained. This allows relatively reliable dating of haplogroups. Additionally, increased levels of Y DNA testing along with substantial increases in sequenced Y DNA for ancient samples, has allowed major advances in understanding the origin, dispersal, and geographic spread of many haplogroups. Given the likely increase in dated ancient haplogroup samples, the detailed places and times of my paternal ancestral migration path from Y-chromosomal Adam onwards is likely to be revised in the future.

My Y DNA results show that I am a member of haplogroup R1b descended from Y-chromosomal Adam 275,000 years ago through haplogroups A1b, BT, CT, F-K, and P. The following diagram is an interesting visualization of the Y haplogroup tree with all its major branches from FamilyTree DNA.

World’s largest Y-DNA Haplotree from FamilyTreeDNA (Image generated using iTOL) (FamilyTree DNA 2020 https://blog.familytreedna.com/human-y-chromosome-testing-milestones/)

In May 2019, the Y-DNA Haplotree passed 20,000 branches, defining over 150,000 unique haplogroups. This makes the FamilyTreeDNA Haplotree the largest and most detailed phylogenetic tree of mankind in the world. The brown area is haplogroup R, R1b is most of R so you can see R1b is a good 40-45% of the tree. This is because the majority of testers to date have European ancestry, not that R1b is the largest haplogroup in the world.

There are at least 13,267 branches on the R1b tree. My Y haplogroup is at the end of one of the branches in the group that meets the circumference where the R1 of R1b is placed. Haplogroup R1b is the most frequently occurring paternal lineage in Western Europe, accounting for 50% or more of all paternal lineages in Europe. It peaks at the national level in Wales at a rate of 92%, at 82% in Ireland, 70% in Scotland, 68% in Spain, 60% in France (76% in Normandy), about 60% in Portugal,] 45% in Eastern England, 50% in Germany, 50% in the Netherlands, 42% in Iceland, and 43% in Denmark.

In a following post, I will summarize the migration path and time line of my paternal ancestors from Y chromosomal Adam down to my most recent haplogroup-defining mutation dated to 510 AD and figure out which wave of migrants into Europe my paternal great-grandfathers were part of and where they were during the ice age.

Y chromosomal Adam

Y-chromosomal Adam is the name given to the patrilineal most recent common ancestor (MRCA) of modern humans. In other words, he was the man from whom all living humans today descend, on their father’s side, and through the fathers of those fathers and so on, back until all lines converge on one person. He is the male counterpart of Mitochondrial Eve, who,lived in north-western Botwsana around 177,000 years ago (confidence interval ± 11,300 years).

When I did my first Y-DNA test in 2012 with the National Geographic’s  National Genographic Project, it gave a date of 60,000 years ago (60 kya) for Y-chromosomal Adam. This was already outdated, as other recent estimates around that time gave dates ranging from 120 to 160 kya. By definition, it is not necessary and highly unlikely that Y-chromosomal Adam and Mitochondrial Eve lived at the same time or in the same location.

However, in 2013 scientists announced the discovery of an extremely ancient Y DNA haplogroup from a sample submitted for an African-American man in the USA.  Y-chromosomal haplogroups are defined by mutations in the non-recombing portions of DNA from the Y chromosome. These mutations accumulate at the rate of roughly two per generation. The accumulation of mutations in the descendants of Y-chromosomal Adam allow us to map out the major branches of the family tree in terms of Y-haplogroups. This discovery adds a completely new branch to the Y-DNA family tree and pushes back the age of Y-chromosomal Adam to around 250 to 300 kya.

There are a number of inconsistent stories about this discovery in popular science magazines and online media, and I’ve relied on what seems to be an authoritative account by TL Dixon [1]. In 2008 an African-American family genealogist, Jacqueline Johnson, submitted samples for several male cousins to Family Tree DNA for Y DNA analysis. The Y DNA for one of these cousins (who has remained anonymous and died in 2013) had no matches in the database. Various genetic genealogists carried out further tests and concluded they had found a new haplogroup which had never been seen before. Jacqueline Johnson traced this cousin’s paternal line back to a former slave named Albert Perry (born between 1819 and 1827) who lived in South Carolina and first appeared on the 1870 census five years after the civil war and the emancipation of slaves.

The sample was then sent for deeper testing to a geneticist at the University of Arizona in Tucson, Professor Michael Hammer. He found similarities between the Perry sample and those from 11 West African Mbo men, from one village in Cameroon, who shared a recent ancestor about 500 years ago. This suggests that it was also home to Albert Perry’s male ancestors, before one of them was taken as a slave across the Atlantic. His team’s research also revealed the extraordinary fact that Perry did not descend from the then Y-chromosomal Adam, and they estimated that his lineage split from all the others about 338,000 years ago, before the emergence of anatomically modern humans [2].

There was speculation at the time that Perry’s Y-chromosome (but not all his DNA) may have been inherited from an archaic human population that has since gone extinct. Unlike the other chromosomes, the lack of recombination along most of the Y chromosome results in fairly stable mutations. Over the last 10 years, it has become understood that mutations occur at different average rates on different sections of the Y chromosome, and that some regions have especially stable average mutation rates. This has allowed much more accurate dating of Y-DNA haplogroups (defined by specific sets of mutations that are passed down from the haplogroup founder in which one or more of the mutations first occurred).

Recent dating analyses have revised the initial age of 338 kya for the new Y-chromosomal Adam, who is the most recent ancestor of Perry’s haplogroup (named A00) and the haplogroups of other living men. These dates have ranged between 160 and 300 kya [3-5]. The most recent of these papers dated Y-chromosomal Adam to 275 kya (95% CI: 241–305 kya). That would make him approximately the 11,065th great grandfather to every man and boy living today.

The most basal haplogroups have been detected in West, Northwest and Central Africa, and Perry’s A00 haplogroup has been found in Mbo men living in western Cameroon. This is all consistent with a location of Y-chromosomal Adam in the north-western quadrant of the African continent. In the migration map for my paternal ancestors which I am working on, I am choosing to locate Y-chromosomal Adam in western Cameroon at the Banyang-Mbo Wildlife Sanctuary, not far from the border with Nigeria.

The red marker shows the location of the Banyang-Mbo Wildlife Sanctuary in western Cameroon

Future discoveries of presently unknown archaic haplogroups in living people may well lead to further revisions in the age and location of a new Y-chromosomal Adam. In particular, because we now know humans interbred with Neanderthals, the discovery of Neanderthal DNA on the Y chromosome would immediately push back the time to the most recent common patrilineal ancestor to at least twice its current estimate.

In 2016, Mendez et al [5] analysed Y-chromosome DNA from a Neanderthal individual from El Sidron, Spain, and investigated its divergence from chimpanzee and modern human sequences. They estimated that the time to the most recent common ancestor of Neanderthal and modern human Y chromosomes is around 588 kya (95% confidence interval: 447–806 kya). However, they also identified protein-coding differences between Neandethal and modern human Y chromosomes, including potentially damaging changes to three genes that produce male-specific minor histocompatibility (H-Y) antigens. These antigens are thought to elicit a maternal immune response during gestation, somewhat like the Rhesus R+ and R- incompatility. It is possible that pregnancies resulting from a male Neanderthal and female human were not viable, and that Neanderthal genes were only passed down from human males mating with Neanderthal females. If that is the case, the Neanderthal Y-chromosome has not crossed to humans and is extinct.

The revised root of the Y-chromosome family tree is is shown in the following diagram. The basal haplogroup is labelled A. The dates shown in the figure for the split between humans and Denisovans, humans and Neanderthal, and Perry’s Y-haplogroup A00, are from a very recent paper which has been posted on bioRxiv [6] in preprint form, but not yet reviewed or published. The authors have carried out the sequencing of the first Denisovan Y chromosomes from two Denisovan specimens as well as the Y chromosomes of three late Neandethals and estimated the ages of the splits of these two species from the modern human line. Because the majority of archaic human specimens preserved well enough for genome sequencing have been female, an analysis of Denisovan and Neanderthal Y DNA has not previously been carried out.

The revised basal haplogroup A with dates from Petr et al 2020 [6].

The figure below shows the locations and ages of the two male Denisovans, Denisova 4 (55–84 ky old) and Denisova 8 (106–136 ky old), and three male late Neandertals, Spy 94a (38-39 ky old), Mezmaiskaya 2 (43-45 ky old) and El Sidrón 1253 (46-53 ky old). The last of these was the Neanderthal used by Mendez et al [4] to estimate the splot of Neanderthals and modern humans at 588 kya. The new paper [6] estimates a much younger split time for Neanderthals of 350 kya and a slightly younger split time for Perry’s Y chromosome (A00) of 250 kya (213-293 kya). The Denisovan split time is much earlier at 700 (607-833) kya.

Geographical locations and ages of the male archaic humans analyzed by Petr et al 2020 [6]

The sequencing of ancient DNA has hugely expanded our understanding of the evolutionary history of Homo sapiens and related human species. It is almost certain that new papers will continue to revise this understanding and the dating of human lineages over the coming years. And it is entirely possible that the discovery of another deep-rooting Y haplogroup could again dramatically change the age and location of our Y-chromosomal Adam.

References

[1] Dixon TL. A00 Cameroon Research Project and Albert Perry’s Y. Posted 15 January 2017 on TL Dixon’s blog “Roots and Recombinant DNA”. Available at https://www.rootsandrecombinantdna.com/2017/01/a00-cameroon-research-project-and.html

[2] Mendez FL, Krahn T, Schrack B, et al. An African American paternal lineage adds an extremely ancient root to the human Y chromosome phylogenetic tree [published correction appears in Am J Hum Genet. 2013 Apr 4;92(4):637]. Am J Hum Genet. 2013;92(3):454-459.  https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3591855/

[3] Elhaik E, Tatarinova TV, Klyosov AA, Graur D. The ‘extremely ancient’ chromosome that isn’t: a forensic bioinformatic investigation of Albert Perry’s X-degenerate portion of the Y chromosome. Eur J Hum Genet. 2014;22(9):1111-1116. doi:10.1038/ejhg.2013.303

[4] Karmin M, Saag L, Vicente M, et al. A recent bottleneck of Y chromosome diversity coincides with a global change in culture. Genome Res. 2015;25(4):459-466. doi:10.1101/gr.186684.114

[5] Mendez FL, Poznik GD, Castellano S, Bustamante CD. The Divergence of Neandertal and Modern Human Y Chromosomes. Am J Hum Genet. 2016;98(4):728-734. doi:10.1016/j.ajhg.2016.02.023

[6] Petr M, Hajdinjak M, Fu Q, Essel E, Rougier H, Crevecoeur I, et al. The evolutionary history of Neandertal and Denisovan Y chromosomes. bioRxiv 2020.03.09.983445; doi: https://doi.org/10.1101/2020.03.09.983445
https://indo-european.eu/proto-indo-european/topic/the-evolutionary-history-of-neandertal-and-denisovan-y-chromosomes/

 

My maternal ancestors – from Eve via ice age Europe to Victorian England

In an early post on this blog, I summarized my maternal-line ancestors and where and when they lived. In the last 6 years, there have been substantial revisions to estimates of the dates associated with these mitochondrial DNA (mtDNA) haplogroup founders, and revisions to the mtDNA haplogroup tree (deep-maternal-ancestry-and-mtdna) and this post provides an update. I am a member of mtDNA haplogroup U5, which is one of nine native European haplogroups stemming from haplogroup U which most likely arose in the Near East, and spread into Europe in a very early expansion. The presence of haplogroup U5 in Europe pre-dates the last ice age and the expansion of agriculture in Europe. Today, about 11% of modern Europeans are the direct maternal descendants of the founder U5 woman. They are particularly well represented in western Britain and Scandinavia. My more recent maternal ancestors were part of the population that tracked the retreat of ice sheets from Europe at the end of the last ice age and re-colonized Britain about 12,000 years ago.

The mtDNA sequence at the root of each haplogroup arose from one or more mutations in the mtDNA of just one woman, and the age of the associated haplogroup gives the time in the past when this specific woman lived. To emphasise that the maternal clan founders were real individuals, I have used the names given to them by Sykes [1] and Oppenheimer [2] and given my own names to the more recent subgroup founders. The Table below summarizes these founders, dates and locations and is followed by brief biographies. The haplogroups are identified by the labels used in Build 17 of the ISOGG mtDNA tree which can be accessed at http://phylotree.org/ [3]. Dates in the table below have been updated using most recent available dating estimates as described in my previous post deep-maternal-ancestry-and-mtdna.

The migration path out of Africa into Europe of the “grandmothers” linking mitochondrial Eve through to Ursula (U5) is shown on a map in my previous post deep-maternal-ancestry-and-mtdna. The subsequent migration from Europe to Britain is shown in the map below.

Figure 1. Migration path of my maternal ancestors from Ursula (U5) to Viviane (410 CE). A map of the earlier migration from mitochondrial Eve to U5 is included in an earlier post.

Updated biographies of my maternal haplogroup great* grandmothers follow below.

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Our Asgardian ancestors

I grew up reading northern European myths and legends, including tales of Odin, Thor, and the other gods of Asgard. I was largely unaware of the Marvel comics appropriation of Thor and other Asgardians as superheros until the Marvel cinematic universe started to hit the big screens in the last 12 years.

Loki, Thor and Odin (from the Marvel Cinematic Universe)

I have only recently come across the growing evidence that an Asgardian was one of our ancestors, way back near the beginning of the evolution of life, when the first eukaryotic cell appeared. Eukaryotes are organisms whose cells contain membrane-wrapped internal structures, such as a nucleus, unlike prokaryotes (Bacteria and Archaea), which have no membrane-bound internal structures.

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Deep maternal ancestry and mtDNA

In February 2014, I did a series of posts on my deep maternal ancestors, identified through a test of mutations on my mitochondrial DNA (mtDNA) which is inherited only from the mother. This test was carried out by Ancestry.com, who have since discontinued tests of mtDNA and Y-chromosome DNA. Costs of DNA tests have dropped dramatically since then, and late last year I ordered an mtDNA test from FamilyTreeDNA (www.familytreedna.com) which carried out a full sequencing of the mitochondrial DNA.

As well as the DNA that makes up the chromosomes in the nuclei of our cells, we also have another type of DNA called mitochondrial DNA (mtDNA). The mitochondria are organs located outside the cell nucleus which convert sugars into energy.  Mitochondria have a small circular loop of DNA, containing only approximately 16,569 base pairs in humans. The circular mtDNA is similar to the DNA of bacteria, and it is thought that mitochondia evolved from symbiotic bacteria that were once free living.

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Mitochondrial Eve – an update

A recently published paper in Nature (Oct 18) has analysed the mitochondrial DNA of 1,200 indigenous Africans living in the southern part of Africa and identified the ancestral homeland of all humans alive today, the place where mitochondrial Eve lived nearly 200,000 years ago. More on that below, but first some background.

In February 2014, I did a series of posts on my deep maternal ancestors, identified through a test of mutations on my mitochondrial DNA (mtDNA) which is inherited only from the mother. These mutations allowed me to track back through time to mitochondrial Eve, the single woman from whom all humans alive today descended through their female line (mother to mother to mother….).  Specific mutations on the mtDNA define maternal haplogroups, and the founder of a given haplogroups is the specific individual woman in which the defining mutation occurred. All members of a given haplogroup trace their maternal ancestry back to this founder.

DNA tests have become much less expensive, and can include much more detailed testing. In the last three months, I’ve redone a test on my mtDNA and also on my Y DNA, which is inherited only down the male line (father to father to father….). I am still digesting the results of these tests, and will post on them in the near future.  One of the first things I discovered was that the dates associated with haplogroup founders have been revised over time, and as more and more test results are available, and that the terminology used for identifying haplogroups has also evolved.  I also came across very recent research which has pinned down the location where mitochondrial Eve lived, as well as revised estimates of the time period in which she lived.

Haplogroup U5 – the oldest of seven native European haplogroups

My mtDNA haplogroup is U5, the oldest of the seven native European haplogroups. Haplogroup U most likely arose in the Near East, and spread into Europe in a very early expansion, giving rise to seven native European haplogroups, including U5. The presence of haplogroup U5 in Europe pre-dates the last ice age and the expansion of agriculture in Europe. Today, about 10% of modern Europeans are the direct maternal descendants of the founder U5 woman, who has been given the nickname Ursula*. They are particularly well represented in western Britain and Scandinavia.

Ancestral migration path of maternal ancestors for haplogroup U5

Haplogroup U in turn is descended via haplogroups R and N from haplogroup L3, which is associated with a migration of humans out of Africa around 70,000 to 50,000 years ago. The dominant theory of human origins, the “recent African origin” theory, proposes that all modern non-African populations are substantially descended from populations of H. sapiens that left Africa after during that time period. H. sapiens most likely developed in Africa between 300,000 and 200,000 years ago, and there were at least several “out-of-Africa” migrations of modern humans, possibly beginning as early as 270,000 years ago. These early dispersals may have died out or retreated, although some paleoanthropologists argue that they possibly interbred with various other local hominid species and with later humans from “recent-out-Africa” and it just so happens that all the maternal lineages trace back to “recent-out-Africa”. Of all the lineages present in Africa, only the female descendants of Lara*, founder of the L3 haplogroup, are found outside Africa. If there had been several migrations, one would expect descendants of more than one lineage to be found.  Of course, all this could be upturned if descendants of other African lineages are found outside Africa, and can be traced back to earlier migrations.

Mitochondrial Eve (haplogroup L)

Mitochondrial Eve (mt-Eve) is a member of Haplogroup L and lived just before the divergence of macro-haplogroup L into L0 and L1–6 (see diagram below). Today the haplogroup L0 and its offshoots are found mainly in southern and eastern Africa, with particularly high frequencies among the San people (bushmen) of Botswana, Namibia and other countries of southern Africa.

Haplogroup L1 is found in West and Central sub-Saharan Africa. The descendants of haplogroup L1 are also African haplogroups L2 and L3, the latter of which gave rise to all non-African haplogroups.

Phylogenetic tree for mtDNA Haplogroup L, commencing with mitochondrial Eve, the most recent common maternal ancestor (MRCA) of all humans.

A recent paper by Chan et al. in Nature (October 2019) [1] analysed the genomes of more than 1,200 indigenous Africans living in southern Africa and claim to have identified precisely where and when the L haplogroup split into L0 and L1 and when these groups migrated from their homeland.

Chan et al. identified this homeland as Makgadikgadi, a vast wetland some 120,000 square kilometers in area, or roughly twice the area of Lake Victoria, Africa’s largest lake today. Mitochondrial Eve and her descendants lived in this region for about 30,000 years (from 200,000 to 170,000 years ago) before the L0 lineage split into its first subgroup. Today, Makgadikgadi is one of the largest salt flats in the world. Climate models suggest that, 200,000 years ago, it was a fertile oasis.  The map  shows the overall location of Makgadikgadi in southern Africa, and the following map shows  a more detailed view.

Satellite view of the Makgadikgadi salt pans. This area is located about 250 km south of Victoria Falls close to the borders of Zambia, Zimbabwe and Botswana.

Chan et al [1] date the deepest rooting L0 branch to 200,000 years ago (with 95% confidence interval 165,000 – 240,000 years ago).  I have reviewed the most recent comprehensive dating of maternal haplogroups and found that the dates in Fu et al (2012)  [2] and Behar et al [2013] were in reasonably good agreement.  I have used dates from Behar et al, which give a date of  176,700 years ago (confidence interval ± 11,300 years) for mitochondrial Eve, and 136,300 (± 11,700) years ago for L1. This is substantially earlier than the date of the recent out-of-Africa dispersal of L3 around 65,000 years ago.

The Okavango delta, in north-west Botswana, looks very similar to how Makgadikgadi would have looked 170,000-200,000 years ago. Credit: Diego Delso, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=75769486

Migrations from the Makgadikgadi homeland

The Makgadikgadi wetlands were large, wet, and lush with vegetation. They would have provided an ideal home for wildlife and for early humans, including mt-Eve. So why did some migrate?  Around 130,000 years ago, there was a major climatic shift associated with the end of the penultimate glacial period. This led to higher rainfall and created “green corridors” leading to the northeast and to the southwest.  In particular, it appears that the ancestral founder of the L1 haplogroup lived around 136,000 years ago among a group that had migrated north into Zambia, and by around 70,000 years ago her descendents had made their way north to the horn of Africa, where Lara (L3 haplogroup founder live).

The “green corridors” proposed by Chan et al [1] helped lead humans out of the ancestral homeland

Chan and his group have extrapolated the likely location of mt-Eve’s homeland from the present-day distribution of the L haplgroup in Southern Africa, and it is always possible that future data may lead to revisions of this conclusion. However, multiple sets of evidence lead to the conclusion that mt-Eve was among the ancestors of the San people of southern Africa, although of course we likely will never know for sure exactly where she lived. And this was not the only ancestral human homeland. Y-DNA evidence suggests that Y-Adam lived in West Africa in a time period even further in the past (this will be subject of a future post) and of course, there may be other ancestral homelands associated with the many other ancestral lines than the purely maternal and paternal.

The San people of southern Africa have one of the most oldest maternal DNA lineages on Earth. They share the Haplogroup L with mitochondrial Eve who lived in northern Botswana nearly 200,000 years ago.


* Bryan Sykes in his 2001 book The seven daughters of Eve gave names to each of the women who founded the seven native European haplogroups, and also names to some of their ancestral haplogroups. He chose names that began with the letter by which the haplogroup was identified. Oppenheimer (The Origins of the British: A Genetic Detective Story, 2006) followed this example and also gave names to both mtDNA and Y-DNA haplogroups. To emphasise that the maternal clan founders were real individuals, who were my ancesters, I have used these names and given my own names to the more recent subgroup founders.

References

[1] Chan EKF, Hardie RA, Petersen DC, Beeson K, Bornman RMS, et al. (2015) Revised Timeline and Distribution of the Earliest Diverged Human Maternal Lineages in Southern Africa. PLOS ONE 10(3): e0121223.
https://doi.org/10.1371/journal.pone.0121223

[2] Fu Q, Mittnik A, Johnson PLF, et al. A revised timescale for human evolution based on ancient mitochondrial genomes. Curr Biol. 2013;23(7):553–559. doi:10.1016/j.cub.2013.02.044
https://www.cell.com/current-biology/fulltext/S0960-9822(13)00215-7?code=cell-site

[3] Behar D, van Oven M, Rosset S, et al. A “Copernican” Reassessment of the Human Mitochondrial DNA Tree from Its Root. Am J Hum Genet. 2012;90(5):936. doi:10.1016/j.ajhg.2012.04.007
Open ArchiveDOI:https://doi.org/10.1016/j.ajhg.2012.03.002

Maternal ancestors: Bronze age, iron age, Roman Britain

This post has been superceded by a new post my-maternal-ancestors-from-eve-via-ice-age-europe-to-victorian-england which contains latest information from a recent more detailed analysis of my mtDNA together with revised and updated dates and locations of haplogroup founders.

This is the last of a series of posts on my deep maternal ancestors, identified through analysis of mitochondrial DNA (mtDNA) which is passed only from the mother to the child and so provides a trail of maternal ancestors identifiable through the mutations accumulated in the mtDNA. In this post I summarize the “recent” maternal ancestors who lived through the beginnings of agriculture in Britain, the British bronze age, the British iron age, the Roman occupation, and post-Roman Britain.

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Maternal ancestors: ice age Europe and Britain

This post has been superceded by a new post my-maternal-ancestors-from-eve-via-ice-age-europe-to-victorian-england which contains latest information from a recent more detailed analysis of my mtDNA together with revised and updated dates and locations of haplogroup founders.

In my previous post on my deep maternal ancestors (https://mountainsrivers.com/2014/02/16/deep-maternal-ancestors-out-of-africa-into-ice-age-europe/) I summarized the “grandmothers” who contributed specific mutations to my mtDNA that allow me to trace them (and approximately when and where they lived) all the way back  to Mitochondrial Eve, the most recent common maternal ancestor of all living humans. These women were real and specific individuals, and Sykes and others have given the older ones specific names (usually starting with the letter of the haplogroup they founded).  I have followed this by giving names to the founders of the subgroups to which I belong. In this post, I  give a brief biography of each of these ancestral grandmothers, starting with Mitochondrial Eve, placing them in evolutionary, geographic, and climatic context. Continue reading