[rjpaints]

I have bloodtyping results back on my mare what do they mean? Here they are AL: AB
GC:FS

Markers recognized by techniques used AL:A,B,I GC:F,S

this test was done by UC Davis!

[Blistering Winds]

Sorry, I don't know much about bloodtyping.

What kind was done? Genetics?

Does UC Davis not send out something on how to read it if you want?

[Bubba]

They should have given you some info about how to read ther esults they found. If not, maybe you could try calling or e-mailing them and asking them directly? There website is here:

http://www.vgl.ucdavis.edu/

...and might give you some clues as well.

[cassidy]

i would give them a call an ask them to explain it at least then you no you will be getting it right

[Comet]

We used to use Maxxam for testing in Canada but then we were informed that they were discontinuing blood typing and tobiano testing. So, once again we used UC Davis.

This was a few years back but they might still have the same format for the testing results. They would state at the bottom that it was probable that the horse was homozygous or probable that it was heterozygous for the tobiano gene. Not exact words but close.

Your horse looks like it may be AB informative as they call it. Informative meaning that they were able to distinguish the blood markers. This is helpful for coming to conclusive results when testing her offspring if you were to breed her.

If nothing else, give them a call. They were always helpful and professional.

[Bubba]

I found this under the FAQ page of the UC Davis VGL website. I hope I did the quotes right!

I am considering buying a yearling colt. Obviously he has no foals. Are there any tests that can tell me if he is homozygous for tobiano? Genetic markers linked to tobiano may help, but cannot prove homozygosity since there is no direct test for the tobiano gene. The tobiano gene is very closely linked to the Albumin and GC genes. Generally, the "B" variant of AL and the "S" variant of GC mark the chromosome with the tobiano gene, although exceptions do occur. These markers also occur in solid color horses and so do not provide a direct test for tobiano. The tobiano zygosity analysis test we provide is based on tracking the marker combinations from both parents to their offspring. A tobiano with tobiano parents (of Quarter Horse breeding) that also has only the markers AL-B and GC-S is five times more likely to be homozygous for tobiano than to be heterozygous. If both parents are known to be heterozygous for tobiano, and both are AL-AB and GC-FS, then their AL-B and GC-S tobiano offspring is highly likely to be homozygous for tobiano (greater than 90% chance).

What does it mean if a horse's markers are "uninformative" for the tobiano test? The common marker combination for tobiano associated with homozygosity is AL-B, GC-S, but not all B/S tobianos are homozygous. Some heterozygous tobianos (for example, with a Quarter Horse parent or solid offspring) have the B/S combination and are uninformative for purposes of the zygosity analysis. An uninformative horse does not mean that it is unsuitable as a breeding horse; it only means that the marker test cannot be applied to predict the zygosity of the offspring. What is "AB informative"? The term "AB informative" was coined by Portland State University, who only use the AL marker to identify horses that are heterozygous for the tobiano pattern and whose markers linked to the tobiano gene are also heterozygous or "informative". When Dr. Bowling developed the test for tobiano homozygosity, she found that both AL and GC are tightly linked to tobiano. VGL uses both markers in our analyses. A heterozygous horse with AB markers would be informative for tobiano breeding because most commonly the AL-B is linked to tobiano and the AL-A is non-tobiano. Using the AL and GC markers combined provides more reliable information to determine the linkage phase. A heterozygous horse may be "informative" for breeding purposes in either the AL or the GC marker.

[shell]

Are you bloodtyping to prove sire and dam for registration?

[rjpaints]

No these results are to prove if she is homozygous or not. I have read it and read it and what i think it mean is she is AB informative and when bred to a homozygous stud which she is the foal could be homozygous! Do you guys get thiss idea too?

[Bubba]

Hmm, what I got out of it, I think , is that your mare is *most likely* homozygous (they can't ever be 100% sure, since they cannot actually identify the gene itself, just blood markers *close* to the gene). That would mean her foal will most likely be tobiano .

If she is homozygous, and bred to a homozygous stallion, *yes* that foal will be homozygous as well, without question .

Did you know you can get a homozygous foal from two heterozygous tobianos, though?

[shell]

I have done the test for homozygous black. I sent in mane hair, not blood. Also, the results were clear that my horses had no red factor and were homozygous for black. So, I don't know what company you sent your test to, but UC David was easy and clear with my results.