Comments and speculation on S21 mutation

(last updated 1st  December 2005)

Currently, only ten people are S21 derived or positive out of 42 with S21 results. Five belong to the R1bSTR22Frisian subgroup, two to a closely linked subgroup R1bSTR27, one to R1bSTR3, one to R1bSTR42 and one to a subgroup extremely close to the R1b modal (R1bSTR11). To date, no members of the “Irish” or “Scots” subgroups have been S21 positive. The tabulation of results is shown in Fig 1 below adjacent to a phylogram showing the relationship between the STR clusters. For those interested in the modal haplotype of the various clusters they are summarised in the following tables (phase 3 analysis modal values).

 

A Chi square test was undertaken grouping results from R1bSTR22Frisian and R1bSTR27 with the rest of the R1b clusters. While the numbers are marginal (1 expected cell number was markedly less than 5) after a Yates continuity correction was employed a significant result was observed (p = 2.6 x E-6 ). This result suggests that the STR clustering is providing significantly useful information to predict the S21 SNP allele status.

 

However, in my opinion until we get a better sampling of the R1b clusters, the numbers are still insufficient for any clear cut conclusions. I feel we need to get 2 or more people sampled for each of the S21 negative clusters and 5 or more people sampled from the S21 positive clusters. The following comments should be classed as informed speculation.

 

Selected results for the S21 positive individuals and selected R1b STR clusters of interest are shown below. If the 10 S21+ (derived) individuals are grouped together and a STR modal calculated for their 37 FTDNA markers stored in Ysearch, they show considerable diversity between individuals (differ at 8-17 markers) and with the modal itself (differ at 5-10 markers). Using an “effective” STR mutation rate estimate of 0.0007 and a generation length of 28 years via Dean McGee’s Y-utility http://www.mymcgee.com/tools/yutility.html  provides an estimate that the S21 variant appeared ~9231 years ago, several thousand years after R1b itself. Three clusters R1bSTR20, R1bSTR22Frisian and R1bSTR27 are closest to the S21 modal. There is no surprise for the latter 2, because most members come from these groups, but results from R1bSTR20 have yet to be reported.  I would hazard a guess that individuals within this group will also be found to be S21 positive, but it would be extremely valuable to have confirmation from several individuals. Nichols UY8W4, Lovelace F323W and Blakely BNP5U are unusual individuals being S21 positive and inhabiting separate clusters, from the majority of S21 positives. However, the differences from R1bSTR20 and R1bSTR27 modals are often not marked and it will be interesting to identify if they are aberrant individuals not clustered correctly, or  represent an as yet unidentified, but related group.

 

Relative to their frequency within R1b, the “Scots”, “Irish” and “Frisian” clusters have been tested approximately twice as frequently for S21 than other R1b clusters. This is because it is suspected that the first two clusters represent a fraction of the “aboriginal” inhabitants of Britain and Ireland respectively, who in turn are derived from an R1b Iberian refugia population from the last ice age. The Frisian cluster in contrast may represent an R1b variety that in prehistory after the last ice age resided in the northern European mainland. It is not yet known when the S21 mutation happened, but because of its current frequency within R1b, it was perhaps towards the end of the last ice age, and possibly in a distinct non-Iberian refugia.

 

Many clusters have yet to be sampled and it is still quite possible given the age of the mutation that several separate and distinct unrelated clusters may also be found to be S21 positive as the branching structure of the R1b clusters is poorly resolved.

 

The overall results to date are consistent with S21 being a unique subclade of R1b1c and formed around the end of the last ice-age. It is less certain how well current 37 FTDNA STR haplotypes can be used to define S21 positive individuals, but the tentative evidence suggests that at least some sub-groups may be distinct enough to be identified.

 

Comments and speculation M167

Excitingly, we also now have two members of the subclade R1b1c6 (M167 positive) shown to be negative for S21. M167 (also known as SRY-2627) positive individuals (R1b1c6) are rarely reported and have also been ascribed an Iberian origin (see listserver summary by David Wilson, Hurles et al. 1999 and a summary of the M167 literature). These individuals differ in their 37 marker haplotype at 13 markers. Using the same mutation rate and generation interval as described above provided an estimate of TMRCA of 9072 yr bp, similar to the estimates obtained from reanalysis of data from Beleza et al (2005) of 8198 yrs bp and 9874 yrs bp from Hurles et al. 1999. We need more and better data, but it suggests the SNP is very old. Its frequency is obviously lower than S21 at least in the populations examined to date. Interestingly, ancestors of both individuals came from the south coast of Britain and this suggests contact and trading with northern Spain.

 

Update from Jim Wilson private information on S21

Jim Wilson has been examining individuals from Orkney and has identified 15 S21 positive individuals. Unfortunately only 9 STR markers have been genotyped. Of these 15 individuals, 7 have a pattern consistent with a “Frisian” or associated cluster signature. Some care is needed here because the information is rather tentative. The remaining 8, however, are quite different and more closely resemble R1b clusters R1bSTR42-45 with DYS390=24, DYS391=10 and DYS392=14. To date we have only identified one such individual in the public work (Blakely BNP5U).

 

My tentative summary is that just because you don’t closely match the Frisian modal STR haplotype, does not mean you can assume you will be S21 negative. In fact we may find that several more R1b STR clusters to be S21 positive.  We may also find that the number of STR markers we are using may do a poor job of resolving this subclade.  

 

Table 1. Haplotypes of S21 positive individuals, their modal haplotype and selected Haplogroup R clusters. The R1b clusters chosen are those most distinct from R1b, those close to the S21 modal or containing a S21 individual.

Ysearch Database Configuration - DNA Results Comparison

ID

D
Y
S
3
9
3

D
Y
S
3
9
0

D
Y
S
1
9
/
3
9
4

D
Y
S
3
9
1

D
Y
S
3
8
5
a

D
Y
S
3
8
5
b

D
Y
S
4
2
6

D
Y
S
3
8
8

D
Y
S
4
3
9

D
Y
S
3
8
9
-
1

D
Y
S
3
9
2

D
Y
S
3
8
9
-
2

D
Y
S
4
5
8

D
Y
S
4
5
9
a

D
Y
S
4
5
9
b

D
Y
S
4
5
5

D
Y
S
4
5
4

D
Y
S
4
4
7

D
Y
S
4
3
7

D
Y
S
4
4
8

D
Y
S
4
4
9

D
Y
S
4
6
4
a

D
Y
S
4
6
4
b

D
Y
S
4
6
4
c

D
Y
S
4
6
4
d

D
Y
S
4
6
0

G
A
T
A
-
H
4

Y
C
A
-
I
I
a

Y
C
A
-
I
I
b

D
Y
S
4
5
6

D
Y
S
6
0
7

D
Y
S
5
7
6

D
Y
S
5
7
0

C
D
Y
a

C
D
Y
b

D
Y
S
4
4
2

D
Y
S
4
3
8

modal_S21only

13

23

14

11

11

14

12

12

12

13

13

29

18

9

10

11

11

24

15

19

29

15

16

17

18

11

11

19

23

17

15

17

17

37

38

13

12

Nichols_UY8W4

13

24

14

11

11

14

12

12

12

13

13

29

18

9

10

11

11

25

15

19

31

15

17

17

17

11

11

19

23

16

15

16

16

37

38

12

12

Nichols_23UDR

13

23

14

11

13

14

12

12

12

13

13

29

18

9

10

11

11

24

15

19

29

15

16

16

18

11

10

19

23

18

14

18

17

36

39

13

12

Creel_28UTA

13

23

15

12

11

14

12

12

12

13

13

28

14

9

10

11

11

25

15

19

30

14

15

14

18

11

11

19

23

17

15

17

17

38

38

12

12

Ozment_35UQ4

13

23

14

11

11

14

12

12

11

13

13

29

17

9

10

11

11

25

15

19

29

15

15

16

17

11

11

19

23

17

15

17

18

36

38

13

12

Hart_7FZUQ

13

23

14

12

11

14

12

12

11

13

13

30

19

9

10

11

11

23

15

19

29

15

16

17

18

10

10

19

23

18

15

17

17

35

37

13

12

Blakely_BNP5U

13

24

14

10

12

12

12

12

12

11

13

27

18

9

10

11

11

24

15

19

29

15

16

17

18

11

11

19

22

15

15

17

18

35

38

11

12

Lovelace_F323W

13

23

14

11

11

15

12

12

12

13

13

29

17

9

10

11

11

24

14

19

29

14

15

17

18

10

11

19

21

15

14

17

17

37

39

12

12

Lovelace_RJEF9

13

23

14

11

11

14

12

12

12

13

13

29

16

9

10

11

11

24

15

19

27

15

16

17

18

11

10

19

23

17

15

17

17

37

39

12

12

Wade_SFVPS

13

22

14

11

11

14

12

12

12

13

13

30

18

9

10

11

11

24

14

15

28

16

16

17

18

11

10

19

23

17

15

18

17

37

38

13

12

Hightower_UFBVM

13

23

14

11

11

14

12

12

11

13

13

29

18

9

10

11

11

23

15

19

29

15

16

17

18

10

10

19

23

16

15

19

16

37

38

13

12

R1b

13

24

14

11

11

14

12

12

12

13

13

29

17

9

10

11

11

25

15

19

29

15

15

17

17

11

11

19

23

15

15

18

17

37

38

12

12

R1a

13

25

15

10

11

14

12

12

10

13

11

30

15

9

10

11

11

23

14

20

32

12

15

15

16

11

11

19

23

16

16

18

18

34

39

12

11

R1bSTR3

13

23

14

11

11

14

12

12

12

13

13

29

17

9

10

11

11

25

15

19

29

15

15

17

18

11

11

19

22

15

14

16

17

37

39

12

12

R1bSTR11

13

24

14

11

11

14

12

12

12

13

13

29

17

9

10

11

11

25

15

19

29

15

15

17

17

11

11

19

23

15

15

18

16

38

38

12

12

R1bSTR19Irish

13

25

14

11

11

13

12

12

12

13

14

29

17

9

10

11

11

25

15

18

30

15

16

16

17

11

11

19

23

17

16

18

17

38

39

12

12

R1bSTR20

13

23

14

11

11

14

12

12

12

13

13

29

18

9

10

11

11

26

15

19

29

15

15

16

17

11

11

19

23

16

15

17

18

37

38

12

12

R1bSTR22Frisian

13

23

14

11

11

14

12

12

12

13

13

29

17

9

10

11

11

24

15

19

29

15

16

17

18

11

10

19

23

17

15

17

17

37

39

13

12

R1bSTR27

13

23

14

11

11

14

12

12

12

13

13

29

17

9

10

11

11

25

15

19

29

15

15

17

17

11

11

19

23

17

15

18

17

37

38

12

12

R1bSTR42

13

24

14

10

11

14

12

12

12

13

13

29

17

9

10

11

11

25

15

19

29

15

16

16

17

11

11

19

23

15

15

17

17

37

38

12

12

R1bSTR47Scots

13

24

14

10

11

14

12

12

12

13

13

30

18

9

10

11

11

25

15

19

30

15

15

17

17

11

12

19

24

16

15

18

17

37

38

12

12

Distance from reference:

Zero

One

Two

Three+

 

Table 2. Genetic distance (infinite alleles model) between individuals and selected clusters

Genetic Distance

ID

m
o
d
a
l
_
S
2
1
o
n
l
y

N
i
c
h
o
l
s
_
U
Y
8
W
4

N
i
c
h
o
l
s
_
2
3
U
D
R

C
r
e
e
l
_
2
8
U
T
A

O
z
m
e
n
t
_
3
5
U
Q
4

H
a
r
t
_
7
F
Z
U
Q

B
l
a
k
e
l
y
_
B
N
P
5
U

L
o
v
e
l
a
c
e
_
F
3
2
3
W

L
o
v
e
l
a
c
e
_
R
J
E
F
9

W
a
d
e
_
S
F
V
P
S

H
i
g
h
t
o
w
e
r
_
U
F
B
V
M

R
1
b

R
1
a

R
1
b
S
T
R
3

R
1
b
S
T
R
1
1

R
1
b
S
T
R
1
9
I
r
i
s
h

R
1
b
S
T
R
2
0

R
1
b
S
T
R
2
2
F
r
i
s
i
a
n

R
1
b
S
T
R
2
7

R
1
b
S
T
R
4
2

R
1
b
S
T
R
4
7
S
c
o
t
s

 

modal_S21only

37

9

8

10

6

10

10

10

5

8

7

8

21

9

10

13

5

3

6

7

12

 

Nichols_UY8W4

9

37

15

13

11

17

14

15

11

14

10

6

20

10

6

14

7

12

7

8

8

 

Nichols_23UDR

8

15

37

16

12

12

15

13

9

11

11

13

21

11

14

14

12

7

12

13

16

 

Creel_28UTA

10

13

16

37

12

14

17

15

11

16

16

12

20

13

12

14

12

12

10

11

13

 

Ozment_35UQ4

6

11

12

12

37

11

13

14

10

14

9

8

19

10

8

13

6

7

6

8

14

 

Hart_7FZUQ

10

17

12

14

11

37

16

15

11

14

8

15

21

15

16

19

13

9

14

13

16

 

Blakely_BNP5U

10

14

15

17

13

16

37

15

14

17

15

13

23

14

13

19

11

13

15

10

15

 

Lovelace_F323W

10

15

13

15

14

15

15

37

10

16

14

11

22

7

13

15

12

9

11

11

17

 

Lovelace_RJEF9

5

11

9

11

10

11

14

10

37

10

10

10

20

9

12

12

8

3

8

9

13

 

Wade_SFVPS

8

14

11

16

14

14

17

16

10

37

12

13

20

16

15

15

13

9

12

13

13

 

Hightower_UFBVM

7

10

11

16

9

8

15

14

10

12

37

12

21

13

12

18

8

8

11

12

14

 

R1b

8

6

13

12

8

15

13

11

10

13

12

37

19

6

2

11

7

9

2

4

7

 

R1a

21

20

21

20

19

21

23

22

20

20

21

19

37

20

19

17

17

21

19

19

18

 

R1bSTR3

9

10

11

13

10

15

14

7

9

16

13

6

20

37

8

12

9

8

6

8

12

 

R1bSTR11

10

6

14

12

8

16

13

13

12

15

12

2

19

8

37

11

8

11

4

6

9

 

R1bSTR19Irish

13

14

14

14

13

19

19

15

12

15

18

11

17

12

11

37

14

12

10

11

15

 

R1bSTR20

5

7

12

12

6

13

11

12

8

13

8

7

17

9

8

14

37

8

6

7

10

 

R1bSTR22Frisian

3

12

7

12

7

9

13

9

3

9

8

9

21

8

11

12

8

37

7

8

14

 

R1bSTR27

6

7

12

10

6

14

15

11

8

12

11

2

19

6

4

10

6

7

37

6

8

 

R1bSTR42

7

8

13

11

8

13

10

11

9

13

12

4

19

8

6

11

7

8

6

37

9

 

R1bSTR47Scots

12

8

16

13

14

16

15

17

13

13

14

7

18

12

9

15

10

14

8

9

37

 

Related

Probably Related

Possibly Related

FTDNA's Interpreting Genetic Distance for 12 Markers

FTDNA's Interpreting Genetic Distance for 25 Markers

FTDNA's Interpreting Genetic Distance for 37 Markers

- Infinite allele mutation model is used
- Values on the diagonal indicate number of markers tested

 

 

Table 3. TMRCA estimates using an effective mutation rate of 0.0007 and a generation length of 28 years

Time to Most Recent Common Ancestor (Years)

ID

m
o
d
a
l
_
S
2
1
o
n
l
y

N
i
c
h
o
l
s
_
U
Y
8
W
4

N
i
c
h
o
l
s
_
2
3
U
D
R

C
r
e
e
l
_
2
8
U
T
A

O
z
m
e
n
t
_
3
5
U
Q
4

H
a
r
t
_
7
F
Z
U
Q

B
l
a
k
e
l
y
_
B
N
P
5
U

L
o
v
e
l
a
c
e
_
F
3
2
3
W

L
o
v
e
l
a
c
e
_
R
J
E
F
9

W
a
d
e
_
S
F
V
P
S

H
i
g
h
t
o
w
e
r
_
U
F
B
V
M

R
1
b

R
1
a

R
1
b
S
T
R
3

R
1
b
S
T
R
1
1

R
1
b
S
T
R
1
9
I
r
i
s
h

R
1
b
S
T
R
2
0

R
1
b
S
T
R
2
2
F
r
i
s
i
a
n

R
1
b
S
T
R
2
7

R
1
b
S
T
R
4
2

R
1
b
S
T
R
4
7
S
c
o
t
s

 

modal_S21only

37

5964

5264

6692

3920

6692

6692

6692

3276

5264

4592

5264

17248

5964

6692

9072

3276

2072

3920

4592

8260

 

Nichols_UY8W4

5964

37

10836

9072

7448

12740

9940

10836

7448

9940

6692

3920

16044

6692

3920

9940

4592

8260

4592

5264

5264

 

Nichols_23UDR

5264

10836

37

11760

8260

8260

10836

9072

5964

7448

7448

9072

17248

7448

9940

9940

8260

4592

8260

9072

11760

 

Creel_28UTA

6692

9072

11760

37

8260

9940

12740

10836

7448

11760

11760

8260

16044

9072

8260

9940

8260

8260

6692

7448

9072

 

Ozment_35UQ4

3920

7448

8260

8260

37

7448

9072

9940

6692

9940

5964

5264

14868

6692

5264

9072

3920

4592

3920

5264

9940

 

Hart_7FZUQ

6692

12740

8260

9940

7448

37

11760

10836

7448

9940

5264

10836

17248

10836

11760

14868

9072

5964

9940

9072

11760

 

Blakely_BNP5U

6692

9940

10836

12740

9072

11760

37

10836

9940

12740

10836

9072

19964

9940

9072

14868

7448

9072

10836

6692

10836

 

Lovelace_F323W

6692

10836

9072

10836

9940

10836

10836

37

6692

11760

9940

7448

18564

4592

9072

10836

8260

5964

7448

7448

12740

 

Lovelace_RJEF9

3276

7448

5964

7448

6692

7448

9940

6692

37

6692

6692

6692

16044

5964

8260

8260

5264

2072

5264

5964

9072

 

Wade_SFVPS

5264

9940

7448

11760

9940

9940

12740

11760

6692

37

8260

9072

16044

11760

10836

10836

9072

5964

8260

9072

9072

 

Hightower_UFBVM

4592

6692

7448

11760

5964

5264

10836

9940

6692

8260

37

8260

17248

9072

8260

13776

5264

5264

7448

8260

9940

 

R1b

5264

3920

9072

8260

5264

10836

9072

7448

6692

9072

8260

37

14868

3920

1484

7448

4592

5964

1484

2660

4592

 

R1a

17248

16044

17248

16044

14868

17248

19964

18564

16044

16044

17248

14868

37

16044

14868

12740

12740

17248

14868

14868

13776

 

R1bSTR3

5964

6692

7448

9072

6692

10836

9940

4592

5964

11760

9072

3920

16044

37

5264

8260

5964

5264

3920

5264

8260

 

R1bSTR11

6692

3920

9940

8260

5264

11760

9072

9072

8260

10836

8260

1484

14868

5264

37

7448

5264

7448

2660

3920

5964

 

R1bSTR19Irish

9072

9940

9940

9940

9072

14868

14868

10836

8260

10836

13776

7448

12740

8260

7448

37

9940

8260

6692

7448

10836

 

R1bSTR20

3276

4592

8260

8260

3920

9072

7448

8260

5264

9072

5264

4592

12740

5964

5264

9940

37

5264

3920

4592

6692

 

R1bSTR22Frisian

2072

8260

4592

8260

4592

5964

9072

5964

2072

5964

5264

5964

17248

5264

7448

8260

5264

37

4592

5264

9940

 

R1bSTR27

3920

4592

8260

6692

3920

9940

10836

7448

5264

8260

7448

1484

14868

3920

2660

6692

3920

4592

37

3920

5264

 

R1bSTR42

4592

5264

9072

7448

5264

9072

6692

7448

5964

9072

8260

2660

14868

5264

3920

7448

4592

5264

3920

37

5964

 

R1bSTR47Scots

8260

5264

11760

9072

9940

11760

10836

12740

9072

9072

9940

4592

13776

8260

5964

10836

6692

9940

5264

5964

37

 

0-252 Years

280-532 Years

560-812 Years

840-1092 Years

- Infinite allele mutation model is used
- Average mutation rate: 0.0007
- Values on the diagonal indicate number of markers tested
- Probability is 50% that the TMRCA is no longer than indicated
- Average generaton: 28 years