Appearance
| Foals | ![]() |
Regular bay color with primitive markings. Leg primitives may be harder to see. |
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Non-dun1 on a bay base causes primitive markings. The dorsal stripe is usually the most notable. |
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Adults |
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Mimics
The dun dorsal stripe goes through the tail, while nd1 dorsal stripes don’t.
Dun is more likely to cause striping at the back of the ears than nd1.
Foals with dun tend to have a darker lower face mask, while nd1 foals have a darker forehead.
Genetics
Bay non-dun1 is the result of a bay base with one or two copies of nd1. Non-dun1 (nd1) is an allele of the TBX3 gene.
Bay nd1:
Bay (E/_ A/_) + nd1/nd1
Bay (E/_ A/_) + nd1/nd2
Dun (D), located on the same gene, is dominant over nd1, so horses could carry nd1 without it being noticeable but still pass it on.
Read more:
Chestnut | Chestnut nd1 | Black nd1
Articles
- Imsland, F., McGowan, K., Rubin, C. J., Henegar, C., Sundstrom, E., Berglund, J., Schwochow, D., Gustafson, U., Imsland, P., Lindblad-Toh, K., Lindgren, G., Mikko, S., Millon, L., Wade, C., Schubert, M., Orlando, L., Penedo, M. C., Barsh, G. S., & Andersson, L.; Regulatory mutations in TBX3 disrupt asymmetric hair pigmentation that underlies Dun camouflage color in horses; Nature Genetics (2015); Doi: 10.1038/ng.3475
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