including tobiano, overo & tovero listings & photos for comparison since overo (Lethal White Overo) does not survive in homozygous form       Wychwood Wild Applause, PtHA #121160 Wychwood Applause. Owned by Wyants Winter Springs (Fall 2005 yearling photo). "Charlie-Horse" is a bay rabicano roan homozygous tobiano, 50% Saddlebred, 48% Arabian, 2% pinto. He is expected to mature close to 13.2 hands. He will be bred to Tennessee Walking Horses to produce "Sunday Afternoon Horses." and maybe even a few fancy sport ponies!       Genetic discussion of Tobiano gene horses: There is no direct DNA diagnostic test available for the tobiano gene, but two serum protein markers, Albumin (AL) and Group-specific component (GC), are closely linked to this gene. By testing a horse, its dam and its sire for these serum proteins, analyzing its pedigree for 3 generations, and reviewing color photos of the subject horse to look for secondary spotting, ("ink spots," "paw prints," "cat tracks"), it is possible to predict the likelihood that a horse is homozygous for tobiano. The Tobiano white marking pattern more or less originates from the tailhead, withers or shoulders, and from the feet. Heads are usually solid colored or with stars, strips or smaller blazes. White will typically cross over the horse's backbone somewhere. It commonly produces 4 white socks, especially when manifested minimally, and therefore can be confused with the sabino. Mules that inherit the tobiano gene usually minimize it into a solid color mule w/ 4 white socks.       Discussion of the Overo gene white marking pattern: When inherited from both parents in homozygous form, the LWO (Lethal White Overo) gene causes a newborn foal to die within hours due to a malformed intestinal tract. Considered survivable in heterozygous form only, the frame Overo gene is typically identified by a "frame" pattern; with the white pattern originating from the side of the ribcage and the face (and for that reason can be confused with the sabino gene). Overos typically have flag-face markings, from bald to apron face, with pigment around eyes being preferred.       Horses can carry any of the Tobiano, Overo or Sabino white marking genes, or all three, making positive identification difficult in some cases. *The Pirate EB 2000 bay pinto Curly pony stallion. Offered for sale. Pirate has one blue eye and one brown eye. Registered ICHO/NACHR, ABC-HB, and National Show Pony. About 46", probably homozygous for tobiano. Pirate has sired three for three curly pinto foals, but he is heterozygous for curl since his mother is a straight mini. Pirate leads, ties, clips, trims, loads, and ground drives. He is available to an approved, experienced breeding home, and we prefer someone who will stand him at stud with artificial insemination. As one of the smallest curly stallions in existence, he deserves to continue siring beautiful curly pony babies. WA The First Aurora GGF. Cremello (homozygous creme), homozygous tobiano. TWHBEA, SSHBEA, NSSHA! RJ ("Rory Junior") has exquisite conformation and a gorgeous head (he was Reserve Champion Junior Model Stallion at the 2004 SSHBEA Spring Championship show). He has a sweet, willing and curious personality, and an admirable pedigree. He is a naturally loose moving horse with a heart of pure gold. He is absolutely stunning in person and gets prettier and more 'showy' every day. He currently stands 14'2 barefoot and is still growing, but will not be a tall horse. We offer a double color guarantee of a dilute (palomino, buckskin, or smokey black) AND tobiano foal (or breed back for free)! TN Homozygous Tobiano Paint Horse Webring Welcome to the homozygous paint horse web ring! We would like to invite everyone who breeds homozygous paint horses or stands homozygous paint horse stallions to join our ring. By bringing breeders and owners together we can create a very resourceful and effective advertisement tool. So Join together with us to promote the only true 100% color guarantee in the paint horse industry! Tobiano UC Davis CA Veterinary Genetics Laboratory discussion of Tobiano genetics & genetic testing. What is a Homozygous Tobiano? presented by Pleasure Gait Farms; the genetic test for homozygosity in the tobiano paint pattern is not directly conclusive. Read more about it here. Journal of Heredity report: Brief communication. Tobiano spotting pattern in horses: linkage of To with AIA and linkage disequilibrium. Homozygous Tobiano Dies of Lethal White! HorseQuest.com. Read more about it here Dispelling the Myths of Tovero Paints. Carolyn Schultz HARLEQUIN RANCH Homozygous Stock Monroe, WI, HorseQuest.com. This piece is what I might fondly label Genetics 101...as it is just to provide some basic knowledge of the Tobiano and Overo patterns, and when they combine....the Tovero. This won't be much on telling the difference between the patterns, but moreso the genetics behind them, and information explaining what I'll be discussing. Overo UC Davis CA Veterinary Genetics Laboratory discussion of Lethal White Overo genetics & genetic testing. Horse breeding programs specializing in overo have particular challenges compared with programs for other white patterns such as tobiano. Not only is there the possibility of producing a solid dark foal without the overo pattern but there is also the risk of producing an all-white foal that dies of complications from intestinal tract abnormalities (ileocolonic aganglionosis). As far as we are aware, overo horses themselves have no specific health risks. While breeding evidence shows that some overos are heterozygous for a gene that is lethal in the homozygous condition, it has not been easy to identify which horses have the overo gene that is associated with the lethal white foal syndrome. Occasionally even solid-colored horses without obvious body spotting patterns have been reported to produce lethal white foals. Clearly the spotting pattern classified as overo is phenotypically and genetically heterogeneous. agouti  |  black  |  champagne  |  creme  |  curly  |  dun  |  grey  |  pearl roan  |  sabino  |  silver  |  spotted (LP gene)  |  tobiano  |  weird  |  email ©2006  Homozygous-Horses.com;  All rights reserved.