Thoroughbred families numbers

[wgc517]

Trying to gain an understanding of the thoroughbred family numbers.

1. What differentiates the 1a family from say the 1b? Or the 2a from the 2b. Are they originally from the same family and then branched off or is there no commonality between them?

2. Would it make sense to breed a sire who has a 1b on his tail female line with a mare that also has a 1b on her tail female line (or any other family numbers that are the same)

3. Why is Ashado a 16g. I tried to see how she fit into that family but can't seem to find a common horse from her tale that is in the 16g line.

[diomed]

The lower case numbers represent a branch(a mare that descends from the same original tap root mare).
The best source to see this are at http://www.tbheritage.com/HistoricDams/EngFoundationMares.html and http://www.bloodlines.net/TB/Families/FamilyNumbers.htm the latter of which has some great links for the branches.
16g Descends from the mare Polly Agnes(1865).

[xfactor fan]

In a perfect world all members of a family should have the same mtDNA. HOWEVER, the world isn't perfect and neither is the stud book. Errors have crept in over the years. A good place to check would be the TB Heritage site, and take a glance at the articles in Genetics titled "Who's your Mama" Which goes into some of the mistakes that have been found.

[vineyridge]

Best internet place for information on family numbers is here:
http://www.bloodlines.net/TB/Families/FamilyNumbers.htm

16g is one of the Agnes lines, and they are one line where MtDNA research has showed there to have been mistakes in the GSB.[/url]

[Pan Zareta]

16g is one of the Agnes lines, and they are one line where MtDNA research has showed there to have been mistakes in the GSB.

The anomalous lineage identified by Hill et al. (2002) in family 16 was in one or more descendants of Lady Alice (br f 1855 x Chanticleer - Agnes x Clarion). It was not found in sampled descendants of her sister Miss Agnes (br f 1850 Birdcatcher), the tap of 16-a from whom all family 16 sub-families except 'f' branch.

[vineyridge]

As to doubling the female family top and bottom, it's one of the many theories out there for breeding. Whether it's particularly effective IN GENERAL doesn't seem to have been proved. It was very productive when La Troienne was doubled tail female and sire's tail female. For example, Buckpasser's best runners were daughters from 1-x mares, as was he--and his best runner daughters were also very good broodmares.

[xfactor fan]

That theory actually makes some sense.

If you think of mtDNA as the "fuel" that powers the racing machine, then selecting for body parts that work with the same "fuel" seems logical.

Provided of course that both sides of the pedigree show some racing ability.

[jeff9061]

Is there a resource where you can look at sires by family number?

[xfactor fan]

Enter the sire in the database, click on the dam, then look at her offspring. They will all be from the same family. Also part of the free service of this database.

[Matchemforever]

Regarding similar female lines, does this work for all of the same number, regardless of letter?

For example, Mahubah, dam of MOW, is 4c, so her dam was obviously. Her dam crossed on Rock Sand, 4n, was a breeding of line 4 on the dam side.

Is that significant or only when the letters match up too?

Mahubah was fairly successful, not just for MOW.

[brogers]

Regarding similar female lines, does this work for all of the same number, regardless of letter?

For example, Mahubah, dam of MOW, is 4c, so her dam was obviously. Her dam crossed on Rock Sand, 4n, was a breeding of line 4 on the dam side.

Is that significant or only when the letters match up too?

Mahubah was fairly successful, not just for MOW.

Matchemforever,

Unfortunately you are falling for a theory that is well and truly disproven. Bruce Lowe's numbering system was a good idea to classify the thoroughbred but unfortunately there are a number of errors - some up to the 1970's - in the general stud book.

Take a look at this scientific paper http://www.equinome.com/publications/Hi ... 202002.pdf

More specifically the paper states.....

"...the coupling of this genetic information with pedigree records strongly indicates that Families 4 (Layton Barb Mare 1670), 11 (The Pet Mare 1697) and 13 (Sedbury Royal Mare 1665) may descend from a single common founder. The founder haplotype in each is identical (Haplotype J), all three were owned by James Darcy, were kept at Sedbury Stud and lived at about the same time.

Further, most historical literature, including GSB entries, entertains this notion, though none is conclusive (Lowe 1913; Wentworth 1938; Prior 1935). The GSB records that a daughter of the Layton Barb Mare 1670 (Family 4) produced two foals. One was unnamed but, bred by James Darcy’s daughter, may have been The Pet Mare 1697 (Family 11). Also, some sources argue that The Pet Mare 1697 may have been a synonym for Grey Royal 1697, granddaughter of the Sedbury Royal Mare 1665 (Family 13).

It has also been persuasively argued that the Family 7 founder, Lord Darcy’s Blacklegged Royal Mare 1710, shared a common ancestress with these three families (Prior 1935), but our results give two different haplotypes (F and J, 11 bp different) and indicate this cannot be the case. However, haplotype matches suggest possible matrilineal relationship between Family 7 and one or more of the founders of Families 2, 8, 16, 17 and 22. Some historical literature infers these five families descend from a single common founder, but no historical records suggest any link with the Family 7 founder.

We propose that as few as 12 founders may have contributed to the major lineages within the 19 thoroughbred families included in this study. However, if we also consider the deep-rooted anomalies, which probably result from confusion at the foundation stages, then Families 5 and 6 both have a contribution from an additional founder (Haplotypes M and N). The deep-rooted Family 9 anomaly (Hapolype G) may best be explained by confusion with the founder of Family 12. In fact, only one anomalous haplotype (Haplotype O, Family 19) in a relatively modern pedigree (19th century – 1980) is not accounted for by a match with another sampled family.

Although each family is expected to have only one founder and this founder is considered to contribute to one family only we have uncovered a web of founder sharing. Female founders, as they are currently understood, may have contributed differently to these 19 families than previously thought. Further, descendants of Maid of the Glen 1858 (1), Hag 1744 (5), the dam(s) of Betty Percival 1715 and Cream Cheeks 1695 (6), a Curwen Bay Barb Mare 1708/1709 (9), Young Camilla 1787 (11), Lady Alice 1855 (16) and Violet 1858 (19) (Fig. 1) may contain a genetic heritage different to that which pedigree information suggests...."

Basically all of Lowe's work (and for that matter Goos, Bobinski and Toru-Shirai) has all be found to have errors in it, some as late as the 1970's so any theory using these numbers to classify, let alone breed on, is on very very shaky ground. It might also pay to invest in a book that was published this July written by Tony Morris and Dr. Matthew Binns for Xmas. It will help any breeder enormously in understanding what made this wonderful beast.

[xfactor fan]

If you are using family numbers to track mtDNA, then it is best to pick a mare after the advent of genetic verification of parents.

For example, you're pretty safe with Somethingroyal. So all the female lines from her should have the same family number and the same mtDNA. The older the taproot mare is the more likely that there are going to be deep seated mistakes.

The letters get attached to the basic family number when there are a large number of horses that trace back to the same female. For example La Troienne is the founder of family 1-x. Her dam Helene de Troie is from family 1-s.
Given the historical time frame you could make a pretty safe guess that members of family 1-x and 1-s have the same mtDNA. Go farther back to the next split, and the odds aren't as good.

The transmission of mtDNA is egg to egg to egg. So if the records are correct then a mare with mtDNA "A" should go back in a straight line to a foundation mare that also has the "A" type mtDNA. What the genetic testing is showing, is that there are errors that have entered the stud books--horses that clearly don't match their stated pedigree. This is where the Bruce Lowe family numbers break down.

Hope this answers your questions.

[Pan Zareta]

Take a look at this scientific paper ....http://www.equinome.com/publications/Hi ... ...However, haplotype matches suggest possible matrilineal relationship between Family 7 and one or more of the founders of Families 2, 8, 16, 17 and 22.

This was one of the first single-breed/type equine mtDNA studies. In the 8+ years since it was conducted several of its co-authors have been involved with similar studies of other breeds/types (one of several examples being the 2006 study of the Irish Draught available online at http://www.equinome.com/publications/McGahern%20et%20al%202006_2.pdf) as well as done additional work, some unpublished, on TB haplotypes. From refinements to haplotype definitions apparent in the work since 2002 it appears that families 7,17,and 22 almost certainaly do not share a founder with families 2,8,and 16. Including another anomalous lineage that has turned up within one of those six families there are at least three founders present therein. More than three is a distinct possibility.

[diomed]

Byron. Can you give me the actual title of that publication. I am very interested in reading it if I can afford it. Thanks in advance.

[Pan Zareta]

Diomed, it's the 2002 report ("History and integrity of thoroughbred dam lines revealed in equine mtDNA variation") from the study by Hill, et al. Click on the link in Byron's msg. above. It'll take you right to it. Full text. Free.