Father to Son documented genealogy V LDNA test results

I received my son Edward's Living DNA results yesterday, 26 days before the deadline (albeit second sample as first failed. Edward was born severely disabled with severe development delay and doesn't always want to give a swab sample). Here I review all of the Living DNA results against what I believe ancestry is based solely on documented genealogical sources. These documented sources are supported only by family history, interviews, thirty years of documentary research - much of it very local, photographs (likenesses), social background (mainly rural working class, many very localised), local social history, and also in my case by DNA cousin matching:



NPEs and genealogical mistakes (particularly over six generations ago) are possible. However, bearing in mind the above factors, I feel that I have a reasonably good documented record to compare DNA-tests-for-ancestry against.

The two tests in the table below, are my son Edward (left), and myself (right). We are both British by nationality and English by ethnicity. We live in East Anglia, home of many of our documented ancestors. I am mainly of East Anglian ancestry, but with some Oxfordshire, Berkshire, Northants, and Swiss lines. Edward's mother by ancestry is half English (Berks, Wilts, East Anglia, Beds, Somerset) and half Irish.

The "actual documented ancestry" are percentages divided into LDNA sub regions, based on Generation 6 (32 x 3rd great grandparents) with some references to Generation 7 when noteworthy.



Discussion.

Living DNA has made great commercial headway through the use of the POBI dataset, that had been acclaimed by the original team, as demonstrating a distinguishable pattern that aligned well with the Anglo-Saxon period British kingdoms. The reference samples were well chosen, with geographically local born grandparents, and a bias to rural testers over urban (that see more mobility). However, LDNA, we know, have made lot's of alterations with their sub regions.

In both the case of Edward's and my documented East Anglian ancestry, the LDNA saw less than 50% of what I'd expect. I believe that some of our EA went elsewhere - Lincs, SE England, Germanic, Scandinavian, etc.

Edward got a big chunk of Lincs and SE England that I just do not think is real.

I got 10% Tuscan that I don't believe. Something could however correlate to a Swiss 3 x great grandparent. But that percentage? I know it is possible. Edward got no Tuscany.

Edward, with his 25% actual Irish ancestry received 98% GB & Ireland. His father, myself, although 97% actual, received only 70% GB & Ireland. I think that rather like with other test companies - Ireland, Scotland, and Wales look more "British" than do the English on tests. Yet Edward only received a mere 2% Irish on the test! That is an even more serious underscore.

Before I tested with Living DNA, I really was starting to lose faith in autosomal DNA testing for general ancestry. When Living DNA launched, my hopes were raised that with the right references, computing power, and chips, that one day, they could be much more accurate and meaningful than they have been up to now.

After Edward's results, I'm starting to lose a bit of faith again. I feel that these tests are good for pin pointing a corner of Europe at best. Beyond that, there may be average PCA plots, but they are far too fuzzy to base "ancestry composition", my origins", or "ethnicity estimate" percentages on with any degree of certainty or accuracy. Fun yes. Useful to build a personal DNA "ancestral population flavour and PCA plot" yes. But that's all. Beyond that is a roll of the dice. Too many testers take their results far too literally. Too many testers also display brand loyalty.

As for haplogroups, Edward's results were disappointingly basic.

Y-DNA L1

mtDNA H (only 4 mutations listed on the csv file).

Which is more accurate AncestryDNA or 23andMe?

I've been researching my ancestry, on and off, for about 30 years. That included interviewing elderly relatives, family histories, photographs, documents, etc. It progressed onto BMD certificates, Census, and many, many visits to local record offices, churches, and archives across Britain in order to examine parish registers, transcripts, minute books, etc.

These days I have the luxury of online genealogical resources, and the ability of searching online data bases. To cut a long story short, I have accumulated a family history that includes the names of 279 recorded, direct ancestors, 277, of which lived in South East England, particularly in the East Anglian County of Norfolk (the other two were a Swiss 3 x great grandparent and his named father).

At Generation 6 (3 x great grandparent), I can say that on paper, I am 97% South East English (including 75% East Anglian), and 3% Swiss. In other words, pretty much of local East Anglian ancestry. Here is a map showing my recorded ancestors - blue via my father (minus the few in Switzerland), red via my mother:

Okay, I will still have some mistakes in my genealogical research, particularly on more distant lines, where records start to be come more scarce and have less survival. There would also be some NPEs (non parental events). However, if I compare my pedigree with DNA matches / cousins that share common ancestors both in segments and on paper trails, I get this (shaded areas verified with DNA matches to paper trails):
So there is a reasonable verification there.

That is my background. The results? Remember, Generation 6:

97% English
3% Swiss

Well before phasing, 23andme gave me:

100% European: 94% NW European. 3% Southern European. 3% Broadly European. Broken down to:
32% British & Irish
27% French & German
7% Scandinavian
29% Broadly NW European
2% Broadly Southern European (including 0.5% Iberian)

After phasing with a surviving parent, it adjusted to:

100% European: 96% NW European. 2% Southern European. 2% Broadly European.
38% British & Irish (23% from father, 15% from mother)
24% French & German (13% from father, 11% from mother)
0.8% Scandinavian (from mother alone)
34% Broadly NW European (22% from father, 12% from mother)
2% Broadly Southern European (1% from father, 1% from mother)

Not very impressive is it?

AncestryDNA gave me:



Still way off, but a lot closer and more precise than 23andme. They also assigned me both to the Southern England Genetic Community, and to the East Anglia & Essex Genetic Community, perfectly correct.

Therefore in summary - I've come to the conclusion that NO current autosomal DNA test for ancestry is capable of accurately predicting your ancestry below a very large region, such as NW Europe - unless your ancestors belong to a particularly well defined population that avoided medieval admixture. They are all inaccurate. More important to me now is that they have fat databases of testers, with a system of searching them alongside family trees, ancestor locations and surnames. However, side by side - for my results, and weighed simply against recorded family history, I have to pronounce AncestryDNA/.com to be more accurate than 23andme.

Genetic Genealogy - DNA Relative Matches

I have new DNA cousin "matches".  This is a very important avenue of DNA testing for genealogy and ancestry that I have simply missed until recently.  Up to now, I've concentrated on DNA testing for general ancestry (or ethnicity as some businesses will call it).  The problem was that I first tested with 23andme, and simply, using their heavy USA customer base, and user unfriendly "experiences", I couldn't find any DNA relatives that actually had paper trails that could correlate to my own.

One of the problems is I feel, is that an awful lot of Eastern English migration to the Atlantic Coast of North America, occurred very early - late 16th to early 18th centuries AD.  As a result, although some generous matching systems (such as 23andme's) suggests much more recent shared ancestry, in reality, our links to our distant USA cousins are so old, that all they do is reflect that my distant cousins have Puritan, New England, and Virginian ancestry from Eastern England.  Even for those that do claim to trace ancestry to those pilgrim fathers - I can't.  Certainly not for the thousands of my direct ancestors for Generations 11 - 14.  I don't think any of us can.  Chuck in a bit of genetic folding, and all that these distant relationships is really telling us is, that we both have some ancestry from south east England between 300 and 600 years ago.

Then I tested with Ancestry.com, Ancestry.co.uk, AncestryDNA or whatever you want to call that genealogy mega-business.  Their matching system is dumbed down to the frustrating level.  No chromosome locations or chromosome browsers for painting.  Instead however, they have the fattest database of testers and customers - some of whom, will like myself, be subscription slaves to their family tree and documentary genealogical services.  Their matching systems may cut out chromosome data - but on the flip side, you can browse trees, surnames, ancestral locations, of your DNA matches.  As a consequence, I've found 14 matches that share DNA, with predicted relationships - that correlate to a paper trail relationship.

In addition I am now scouring GEDmatch, 23andme, and FT-DNA Family Finder for more relative DNA matches.  I'm recording everything (including chromosome locations when available) onto a spreadsheet.  The image at the top of this page demonstrates my DNA matches where they share ancestry so far.  The darker the shade, the stronger the verification.

I'm starting to see how this is a better tool to understanding, or verifying ancestry, than any stupid ethnicity / ancestry composition by DNA.  Family isn't always biological.  However, finding a genetic correlation is the ultimate evidence to strengthen a tree.  It's fascinating to see actual paper research turning up as segments of inherited DNA on matches.

Generation Eight. The great great great great great grandparents.


Above, the parish church of Strumpshaw in Norfolk.

5 x great grandparents (Generation 8)! Now that is difficult. My percentages really start to fall away at this generation - only 51% named (compared to 89% of Gen. 7). What a challenge.

Right, what I do have:
  1. Edward Brucker. b.1757 Long Wittenham, Berkshire, England.
  2. Elizabeth Brucker (nee Gregory). b.1761 Long Wittenham, Berkshire, England.
  3. brickwall
  4. brickwall
  5. John Edney. b.1743 Whitchurch, Oxfordshire, England
  6. Mary Edney (nee Crutchfield). b.1740 Whitchurch, Oxfordshire, England.
  7. brickwall
  8. brickwall
  9. brickwall
  10. brickwall
  11. David Durran. b.1782 Steeple Ashton, Oxfordshire, England.
  12. Ann Durran (nee Lardner). b.1782. Lived Deddington, Oxfordshire, England.
  13. William Waine. b.1770. Lived Tadmarton, Oxfordshire, England.
  14. Elizabeth Waine (nee ?). Lived Tadmarton, Oxfordshire, England.
  15. brickwall
  16. brickwall
  17. brickwall
  18. brickwall
  19. Henry Baxter. b.1763 Dereham, Norfolk, England.
  20. Mary Baxter (nee Bennett) b.1763 Norfolk, England.
  21. brickwall
  22. brickwall
  23. brickwall
  24. Jane Barker. Norfolk, England
  25. brickwall
  26. brickwall
  27. brickwall
  28. Sarah Barber. b.1782 East Tuddenham, Norfolk, England.
  29. brickwall
  30. Elizabeth Harris. b.1768 Swanton Morley, Norfolk, England.
  31. John Smith. b.1731 Attleborough, Norfolk, England.
  32. Judith Smith (nee Dennis). b.1745 Coston, Norfolk, England.
  33. Richard Smith. b.1775 Attleborough, Norfolk, England.
  34. Mary Smith (nee ?). Lived Attleborough, Norfolk, England.
  35. William Hewitt. Lived Attleborough, Norfolk, England.
  36. Elizabeth Hewitt (nee ?). Lived Attleborough, Norfolk, England.
  37. John Freeman. Lived Attleborough, Norfolk, England.
  38. Anne Freeman (nee ?). Lived at Attleborough, Norfolk, England.
  39. Peter Peach. b.1730. Maxey, Northants, England.
  40. Mary Peach (nee Rippon). b.1734 Maxey, Northants, England.
  41. brickwall
  42. brickwall
  43. Peter Riches. b.1755 Old Buckenham, Norfolk, England.
  44. Mary Riches (nee Harrison). b.1756 Old Buckenham, Norfolk, England.
  45. William Snelling. Lived Carlton Rode, Norfolk, England.
  46. Mary Snelling (nee Lewell). b.1753 Kenninghall, Norfolk, England.
  47. brickwall
  48. brickwall
  49. brickwall
  50. brickwall 
  51. brickwall
  52. brickwall
  53. brickwall
  54. brickwall
  55. brickwall
  56. brickwall
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  60. brickwall
  61. John Goodram. Lived Morningthorpe, Norfolk, England.
  62. Lydia Goodram (nee Hammond). b.1749 Morningthorpe, Norfolk, England.
  63. brickwall
  64. brickwall
  65. John Curtis. Lived Hassingham, Norfolk, England.
  66. Ann Curtis (nee Annison). Lived Hassingham, Norfolk, England.
  67. John Rose. b.1775 Strumpshaw, Norfolk, England.
  68. Martha Rose (nee Rowland). b.1779 Strumpshaw, Norfolk, England.
  69. Benjamin Larke. b.1751 Cantley, Norfolk, England.
  70. Mary Larke (nee Marsh). b.1769 Norfolk, England.
  71. Thomas Dingle. b.1757 Moulton St Mary, Norfolk, England.
  72. Mary Dingle (nee Ginby). Lived Strumpshaw, Norfolk, England.
  73. Henry Rose. b.1779 Strumpshaw, Norfolk, England.
  74. Margaret Rose (nee Ling). b.1781 Acle, Norfolk, England.
  75. brickwall
  76. brickwall
  77. brickwall
  78. brickwall
  79. Benjamin Merrison. b.1759 Repps-with-Bastwick, Norfolk, England.
  80. Lydia Merrison (nee Norton). b.1774 Strumpshaw, Norfolk, England.
  81. brickwall
  82. brickwall
  83. John Briggs. b.1753 North Burlingham, Norfolk, England.
  84. Elizabeth Briggs (nee Jacobs). Lived Strumpshaw, Norfolk, England.
  85. brickwall
  86. brickwall
  87. brickwall
  88. brickwall
  89. Alexander Goffen. b.1705. Lived Rollesby, Norfolk, England.
  90. Anna Goffen (nee ?). Lived Strumpshaw, Norfolk, England.
  91. James Shepherd. Lived Reedham, Norfolk, England.
  92. Judith Shepherd (nee Maye). b.1749. Lived Reedham, Norfolk, England.
  93. William Nichols. Lived Halvergate, Norfolk, England.
  94. Elizabeth Nichols (nee Thurkettle). lived Halvergate, Norfolk, England.
  95. brickwall
  96. brickwall
  97. Thomas Tovel. Lived Wrentham, Suffolk, England.
  98. Hannah Tovel (nee Brown). Lived Wrentham, Suffolk, England.
  99. George Smith. Lived Toft Monks, Norfolk, England.
  100. Elizabeth Smith (nee Wittham). Lived Toft Monks, Norfolk, England.
  101. brickwall
  102. brickwall
  103. brickwall
  104. brickwall
  105. brickwall
  106. brickwall
  107. James Porter. b.1727. Lived at Blofield and Limpenhoe, Norfolk, England.
  108. Elizabeth Porter (nee Mollett). Lived at Blofield and Limpenhoe, Norfolk, England.
  109. William Springall. Lived at Strumpshaw, Norfolk, England.
  110. Susanna Springall (nee Mingay). Lived at Strumpshaw, Norfolk, England.
  111. Jacob Wymer. b.1756 Moulton St Mary, Norfolk, England.
  112. Elisabeth Wymer (nee Moll). Lived at Moulton St Mary, Norfolk, England.
  113. brickwall
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  117. John Thacker. b.1764 Woodbastwick, Norfolk, England.
  118. Ann Thacker (nee Hewitt). b.1774 Salhouse, Norfolk, England.
  119. brickwall
  120. brickwall
  121. Abraham Daynes. Lived at Wicklewood, Norfolk, England.
  122. Elizabeth Daynes (nee Moore). b. 1748 Wymondham, Norfolk, England.
  123. brickwall
  124. brickwall
  125. brickwall
  126. brickwall
  127. Robert Page. b.1752 Wymondham, Norfolk, England.
  128. Elizabeth Page (nee Hardment). b.1751 Bunwell, Norfolk, England.


Who were my great great great great grandmothers? Generation 7 Female ancestors

Above.  One of my daughters posing in workhouse pauper attire, in the very workhouse that some of her own ancestors lived.  Gressenhall Rural-Life Museum, Norfolk.

Here I will attempt to list as many of my 4 x great grandmothers, who they were, where they lived, and something about them.

  1. Elizabeth Brooker (nee Seymore).  b.1797 Drayton, Oxon. England.  Mother to seven children.  Wife of an agricultural labourer.
  2. Hannah Edney (nee Hedges)  b. 1784 Enstone, Oxon, England.  Wife of a thatcher.
  3. Brickwall.  Switzerland.  Wife of a copper smith.
  4. Susannah Durran (nee Waine) b. 1809 Tadmarton, Oxon, England.  Wife of a tailor, mother of seven.
  5. Anne Bennett (nee Neale).  b. 1786 Norfolk, England.  Farmer's wife.
  6. Frances Baxter (nee Shilling). b. 1778 Gressenhall, Norfolk, England.  Bricklayer's wife and mother of four.
  7. Mary Barker (nee Bligh). b. 1797 Scarning, Norfolk, England.  A shoe maker's wife.
  8. Jemima Barber (nee Harris).  b. 1800 Swanton Morley, Norfolk, England, an agricultural labourer's wife, and mother of eight.
  9. Mary Smith (nee Smith).  b. 1775 Attleborough, Norfolk, England.  An agricultural labourer's wife, and mother of seven.
  10. Elizabeth Hewitt (nee Freeman).  b. 1779 Attleborough, Norfolk, England.  An agricultural labourer's wife, and mother of five children.
  11. Ann Peach (nee ?)  b. 1779. Northants, England.  Wife of a Shepherd, mother of four.
  12. Elizabeth Riches (nee Snelling) b.1781 Banham, Norfolk, England.  Wife of an agricultural labourer, mother of nine children.
  13. Elizabeth Barber (nee ?) Lived at Halesworth, Suffolk, England.
  14. Brickwall
  15. Elizabeth Beckett (nee ?)  b.1770.  Lived at Tasburgh, Norfolk, England.  Wife of an agricultural labourer, mother of seven.
  16. Frances Gooderham (nee ?) b.1790 Saham Toney, Norfolk, England.  Wife of an agricultural labourer, mother of eight.
  17. Mary Ann Curtis (nee Rose) b.1806 Buckenham Ferry, Norfolk, England.  Wife of a marshman and agricultural labourer, mother of nine.
  18. Elizabeth Larke (nee Dingle)  b.1795 Strumpshaw, Norfolk, England.  Wife of an agricultural labourer. Only two children found.
  19. Elizabeth Rose (nee Brooks) b.1806 Postwick, Norfolk, England.  Wife of agricultural labourer, mother of nine.
  20. Hopeful Barker (nee Morrison) b.1804 Lingwood, Norfolk, England.  Wife of an agricultural labourer, mother of eight. 
  21. Susanna Key (nee Briggs) b.1781 Strumpshaw, Norfolk, England.  Wife of an agricultural labourer, mother of four.
  22. Elizabeth Waters (nee Ransby) b.1772 Freethorpe, Norfolk, England.  Wife of a mole catcher, mother of four.
  23. Judith Goffen (nee Shepherd) b.1772 Reedham, Norfolk, England.  Wife of a carpenter, mother of six.
  24. Emily Nichols (nee Beck) b. 1795 Halvergate, Norfolk, England.  Wife of an agricultural labourer, mother of only two known.
  25. Elizabeth Tovell (nee Smith) b.1795 Toft Monks, Norfolk, England.  Wife of an agricultural labourer, mother of six.
  26. Ann Tammas (nee Dove) b.1786 Norfolk, England.  Wife of an agricultural labourer, mother of five.
  27. Ann Lawn (nee Porter) b.1763 Limpenhoe, Norfolk, England.  Wife of an agricultural labourer, mother of four.
  28. Mary Springall (nee Wymer) b.1789 Mouton St Mary, Norfolk, England.  Wife of an agricultural labourer, mother of seven.
  29. Brickwall
  30. Catharine Thacker (nee Hagon) b.1797 Shipdham, Norfolk, England.  Wife of an agricultural labourer, mother of three (died 1832, husband remarried).
  31. Sarah Daynes (nee ?) b.1783 Witchingham, Norfolk, England.  Wife of an agricultural labourer, mother of ten.
  32. Mary Quantrill (nee Page) b.1791 Wymondham, Norfolk, England.  Wife of a weaver, mother of four

What I will also say, is that these ancestors could have had more children, that I have not found baptism records for.  Also, that in addition to looking after the household, and rearing so many children, they would have to contribute to income whenever they could, be it by laundering for others, tailoring, and seasonal casual work on the fields.

Who my great great great great grandfathers were, and what they did. Generation 7. Male ancestors.

Just who were my Generation 7 direct male ancestors - my 4 x great grandfathers?  What were their occupations?  Where were they, and how did they support themselves and their families?

  1. John Brooker. b.1788, Long Wittenham, Berkshire, England. Agricultural labourer.
  2. Thomas Edney. b.1785 Whitchurch, Oxfordshire, England. Thatcher.
  3. John Shawers (Shuarze?). b. circa 1800 Switzerland. Copper smith.
  4. Benjamin Durran. b.1810 North Aston, Oxfordshire, England. Tailor.
  5. John Bennett. Lived Norfolk, England. b.1788. Farmer.
  6. Samuel Baxter. b.1787 Dereham, Norfolk, England. Brick layer.
  7. Charles Barker. b.1795 Dereham, Norfolk, England. Shoe maker.
  8. James Alderton Barber. b.1803 Swanton Morley, Norfolk, England. Agricultural labourer.
  9. Raphael Smith. b.1775 Attleborough, Norfolk, England. Agricultural labourer.
  10. Robert Hewitt. b.1782 Attleborough, Norfolk, England. Agricultural labourer.
  11. John Peach. b.1770 Maxey, Northants, England. Shepherd.
  12. Benjamin Riches. b.1779 Old Buckenham, Norfolk. Agricultural labourer.
  13. Benjamin Barber. b. circa 1772. Lived Halesworth, Suffolk, England. No trade found in records.
  14. Brick wall
  15. John Ellis. b. 1773 Lived in Tasburgh, Norfolk, England. Agricultural labourer.
  16. James Gooderham. b.1786 Hempnall, Norfolk, England. Agricultural labourer.
  17. William Curtis. b.1808 Hassingham, Norfolk, England. Marshman, agricultural labourer, and steam engine driver.
  18. Samuel Larke. b.1795 Cantley, Norfolk, England. Agricultural labourer.
  19. William Rose. b.1804 Brundall, Norfolk, England. Agricultural labourer.
  20. Thomas Barker. b.1801 Moulton St Mary, Norfolk, England. Agricultural labourer.
  21. William Key. b.1778 Postwick, Norfolk, England. Agricultural labourer.
  22. Robert Waters. b.1771 Freethorpe, Norfolk, England. Mole catcher.
  23. Richard Goffen. b.1731 Strumpshaw, Norfolk, England. Carpenter.
  24. John Nichols. b.1786 Halvergate, Norfolk, England. Agricultural labourer.
  25. Thomas Tovell. b.1785 Wrentham, Suffolk, England. Agricultural labourer.
  26. Edward Tammas. b.1774 Langley, Norfolk, England. Agricultural labourer.
  27. William Lawn. b.1761 Norfolk. Lived at Halvergate, Norfolk, England. Agricultural labourer.
  28. William Springall. b.1788 Halvergate, Norfolk, England. Agricultural labourer.
  29. Brick wall
  30. William Thacker. b.1796 Salhouse, Norfolk, England. Agricultural labourer.
  31. Reuben Daynes. b.1781 Brandon Parva, Norfolk, England. Agricultural labourer.
  32. Robert Quantrill. b.1797 Norfolk, Lived Wymondham, Norfolk, England. Weaver.


The Roman Contribution

I took the above photo of a Roman tombstone at Colchester.  It's the image of a Roman cavalry officer, ruling over a defeated Briton.  It had apparently been damaged during the following Boadiccan Rebellion.  No doubt the Iceni-led rebels against Roman authority would have found this image a tad humiliating.  The point that I want to make here though, is that the cavalry soldier that this tombstone commemorates, may have been Roman, may have died in South-East Britain, but actually hailed from what is now Bulgaria!

The archaeological and historical evidence suggests that as a foreigner in Roman Britain, he was far from alone.  There are a number of similar stories, that suggest that Roman Britain was visited by many other people from across the empire -  not only people from what is now Italy and Bulgaria, but also from what is now the Netherlands, France, Greece, Syria, Lebanon, Germany, Spain, Tunisia, Algeria and Iraq.  Visitors appear to have included not just military, but merchants, specialists, politicians - they all occasionally stare out at us from the archaeology and histories of Roman Britain.

We know that they were here.

Previous anthropological investigations at Trentholme Drive, in Roman York identified an unusual amount of cranial variation amongst the inhabitants, with some individuals suggested as having originated from the Middle East or North Africa. The current study investigates the validity of this assessment using modern anthropological methods to assess cranial variation in two groups: The Railway and Trentholme Drive. Strontium and oxygen isotope evidence derived from the dentition of 43 of these individuals was combined with the craniometric data to provide information on possible levels of migration and the range of homelands that may be represented. The results of the craniometric analysis indicated that the majority of the York population had European origins, but that 11% of the Trentholme Drive and 12% of The Railway study samples were likely of African decent. Oxygen analysis identified four incomers, three from areas warmer than the UK and one from a cooler or more continental climate. Although based on a relatively small sample of the overall population at York, this multidisciplinary approach made it possible to identify incomers, both men and women, from across the Empire. Evidence for possible second generation migrants was also suggested. The results confirm the presence of a heterogeneous population resident in York and highlight the diversity, rather than the uniformity, of the population in Roman Britain.

Leach, Lewis, Chenery etal 2009

I could have alternatively used more historical evidence of individuals - the General from Tunisia, the Syrian in Northern Britain, with a Southern British born wife, the York woman that appears to have had mixed African ancestry, etc, the recurrent Greek names, the Syrians, Algerians and Iraqis that patrolled Hadrians Wall.  As Charlotte Higgens stated in Under Another Sky, Journeys in Roman Britain 2013:  

"In Roman Britain, you do not have to look far to find traces of people sprung from every corner of the empire.  Because of the Roman's insatiable desire to memoralise their lives and deaths, they left their mark.  Some fell in love, had children, stayed.  Many no doubt to, were brief visitors, posted to Britannia and then off to the next job, in Tunisia, perhaps, or Hungary, or Spain.  In the Yorkshire Museum is an inscription made by a man called Nicomedes, an imperial freedman and probably Greek, to go by the name.  He placed an altar to the tutelary spirit of the provenance - 'Britanniae sanctae', sacred Britannia.  Also in York, a man called Demetrius erected two inscriptions in his native Greek - one to Oceanus and Tethys, the old Titan spirits of the sea; the other to the gods that presided over the governer's headquarters.  The Roman empire was multicultural in the sense that it absorbed people of multiple ethnicities, geographical origins and religions.  But Roman-ness - becoming Roman, living as a Roman - also involved particular and distinctive habits, architecture, food, ways of thinking, language, things that Romans held in common whether they were living in York or in Gaza.".

South east Britain was a part of the Roman empire for no less than 370 years, and was strongly influenced by it both before and after that membership.  That represents quite a few generations, maybe around 12 to 18 generations.  So in AD 410, as locals in Britannia fretted about their Brexit, Germanic immigration, and were petitioning Rome to send the troops back, some of their pretty distant ancestors, had witnessed the arrival of Rome with the Claudian Invasion.  That's a long time for contact and admixture to drip feed.

Did this long membership of the empire leave a genetic signature in Britain?  The current consensus is no!  We have not yet found anything in the British admixture, that can be ascribed to Roman Britain.  Not on an autosomal DNA level.  The given explanation is that the Romano-British admixture experience was so cosmopolitan, and diverse, that no one contributing population managed to leave a lasting signature.  Each case was apt to be washed away by the phenomena of genetic recombination.  It hasn't left a background admix in modern South-East British populations that has yet been detected and recognised.

However, enthusiasts that test their DNA haplogroups do often find results that are not easily explained by conventional British population history.  Odd haplogroups turn up.  My own Y-DNA, L-SK1414, with a Western Asian origin, is just one example.  Perhaps some of these rogue haplogroups in Britain, are a smoking gun of Roman Imperial experience. 

The site of Venta Icenorum here in Norfolk.