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Who's Your Momma IV: Unique...So Far
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Chart to assist in following the discussion. By E.W. Hill, et.al., "History and Integrity of Thoroughbred Dam Lines Revealed in Equine mtDNA Variation," Animal Genetics 33, 187-294. London: Blackwell Publishing.
For a brief description of the royal stud at Tutbury and a chart of some of Britain's royal rulers and early running horse breeders, visit here.
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Separate and Distinct
The remaining horses tested in the Hill study all appear, thus far, anyway, to have derived from founding mares not related to any other matrilines found in the study, and there appear to be no anomalous varients within the traditionally-accepted family pedigrees of these horses. |
| Family No. |
Founder Mare |
Approximate Date |
Number |
Haplotypes |
Type of Anomaly |
| Family No. |
Founder Mare |
Approximate Date |
Number |
Haplotypes |
Type of Anomaly |
| 3 |
Dam of the Two True Blues |
c. 1690 |
6 |
E * |
-- |
| 10 |
Grey Childers Mare [Fair Helen] |
1741 [c. 1730] |
1 |
B *, |
-- |
| 14 |
Oldfield Mare |
c. 1695 |
7 |
D *, |
-- |
| 25 |
Brimmer Mare |
1699 [c. 1700] |
1 |
I*, |
-- |
*Founder Haplotype.
MOD: Relatively Recent Anomaly in Modern Pedigree;
DR: Deep-rooted Anomaly, Possible Foundation Stage Confusion;
MUT: Posible de novo Mutation
Source: E.W. Hill, et.al., "History and Integrity of Thoroughbred Dam Lines Revealed in Equine mtDNA Variation," Animal Genetics 33, 187-294. London: Blackwell Publishing. For personal use only; otherwise, contact Blackwell Publishing.
Note: Names and dates in brackets represent Thoroughbred Heritage corrections, and are not part of the originally published chart. |
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These are horses whose pedigrees place them in family 3 (Dam of the Two True Blues, c. 1690, 6 horses sampled), haplotype "E;" family 10 (Grey Childers Mare, c. 1741, 1 horses sampled), haplotype "B;" family 14 (Oldfield Mare, c. 1695, 7 horses sampled), haplotype "D;" family 25 (Brimmer Mare, c. 1700, 1 horse sampled), Haplotype "I." For now, then, it seems the pedigrees in the GSBhold true for horses descending tail-female in these families, although testing of additional horses could, at some future date, unearth anomalies not encountered in this first round of mtDNA study. |
These results appear to disprove some of Cedric Borgnis' theories of the 1970s (The British Racehorse, June 1979), in which he set forth a fairly tenuous case for the Layton Barb Mare family (family 4) incorporating Families 8, 10, 12, 16, 18, 19, 25, 18 and 31. The genetics don't appear to support most of this, certainly not in the combinations he suggested.
Neither do they support his theory that family 3 is linked in female descent with Familes 2, 17 and 22, although the latter three do appear to spring from a common founding mare (the "F" variant). Borgnis and others have been misled by a note in the entry of the mare identified in the GSB as a Byerley Turk mare, and by Lowe as the "Dam of the Two True Blues," which stated she was "conjectured"to be the same as a Byerley Turk mare in the Hutton stud at Marske, in the lineage of family 2. Family 3 is, thus far, only represented by the "E" haplotype, and does not appear to have any matrilinear relationship to family 2, or any other family, in so far as the Hill study is concerned.
Borgnis isn't the only historian seduced by apparent serendipity in different families lines. As noted earlier, both the turf writer and historian J.B. Robertson, "Mankato," and the great researcher and historian C.M. Prior believed the horses Lowe placed in Families 7, 11 and 13, by virtue of their GSBpedigrees, were linked maternally, and the genetics are now telling us this most definitely is not so in regard to family 7. Part of Prior's belief in this was based on original material he found in the Duke of Newcastle's stud book, but he, like all who spend time pouring over early pedigrees, made a deductive leap that has proven incorrect. Lowe himself, to whom we largely owe the concept of organizing thoroughbred pedigrees by female lineage, was misled by the information provided by the GSB.
The GSB,on which all thoroughbred breeders rely, is still, despite its flaws, a remarkable document of geneology, though it also appears to have recorded some significant errors. With the enormous power now available to look into the past, provided by the advances in molecular genetics, we now have a chance to correct some wrongs and advance our understanding of the development of the thoroughbred and the mares who have had a lasting influence on the breed. |
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