DBE MUTATION, VOLGOGRAD - NATALIIA ZALESSKAIA

Nataliia Zalesskaia (Cyrridwen cattery) in Volgograd, Russia, breeds Persians and Exotic Shorthairs. In 2019, she started working with a Dominant Blue Eyes mutation. She acquired a blue-eyed, brown patched tabby and white domestic shorthair female, Marusya, aged 4-5 months from a cat shelter and after all health checks she was bred to an Exotic Shorthair black bicolour male. Nataliia wanted to breed her to a solid male but did not have one available at the time. This resulted in 4 F1 kittens, (2 boys and 2 girls), 3 with dominant blue eyes. Marusya gave birth to two more F1 litters from a red bicolour Exotic Shorthair male resulting in a total of 7 kittens, 5 of which were dominant blue-eyed. One of Marusya’s F1 daughters was mated to an Exotic Shorthair male and 2 of the kittens were dominant blue eyes.

The breeding programme was complicated by many of Marusya’s mates having a high degree of white markings. Marusya also carries chocolate and colourpoint. Nataliia worked to reduce or eliminate the high degree of white and retain the Exotic Shorthair type.

The blue eyes are not linked to extensive white facial markings (i.e. white blaze, but no white fur around the eyes), so are not related to conventional white spotting. To prevent confusion, Nataliia does not work with copper-eyed cats from blue-eyed parents, avoids solid white cats and avoids breeding with conventional recessive blue-eye/odd-eye cats (where the eye colour is caused by white spotting gene).There are currently about 30 cats with this gene. It seems to work in a different way to Altai/Topaz and may be a mutation at a different locus. Its appearance is more like the American Ojos Azules as there are almost no odd-eyed cats and there are no latents. When two blue-eyed cats were bred together it resulted in kittens that were completely white, non-viable and with characteristic anomalies, just as occurred in the Ojos Azules.

Also like the American Ojos Azules, the cats with this gene do not have a characteristic facial type (this would have been very evident on Persian/Exotic cats). Marusya’s mutation is a challenging one to work with, not only must blue-eye-to-blue-eye matings be avoided there are almost no odd-eyed cats (this homozygous lethal/disabling situation is not unlike Manx or Fold genes). Nataliia is keeping statistics and is investigating this mutation.