Merle Pattern in Poodles Synopsis by Carol Paragon
Shared by LYNDA N OLIVER·MONDAY, JANUARY 8, 2018
A new but scary trend in poodles. For those that don't know merle is a pattern not a colour, a unique and eye catching one for sure but it is dangerous to our standard poodle breed. Thank you Carol for compiling this informative synopsis in a way we can all understand: As a synopsis of this subject, Merle and Poodles, a number of things need to be considered. Defining Merle from the testing site at UC Davis. note, Poodle is not on the list of breeds that have the mutation. Things to think about. “Merle is an incompletely dominant coat color pattern characterized by irregularly shaped patches of diluted pigment and solid color. Breeds with merle include but are not limited to: Shetland Sheepdog, Collie, Border Collie, Australian Shepherd, Cardigan Welsh Corgi, Catahoula Leopard Dog, Dachshund, Great Dane, Bergamasco Sheepdog and Pyrenean Shepherd. Blue and partially blue eyes are typically seen with merle, and merle dogs often have a wide range of auditory and ophthalmologic defects. Dogs with 2 copies of merle (called double merle) are primarily white and can have multiple abnormalities of skeletal, cardiac and reproductive systems, thus breedings between 2 merle dogs are discouraged to avoid producing double merle offspring. Merle is governed by a SINE insertion in the Pmel17 or Silver (SILV) gene. In the horse, a mutation in this gene results in eumelanin pigment dilution and is also associated with eye abnormalities.”
1) Anyone who sells a fluffy puppy with this pattern, is not selling a Purebred Poodle. It is an overpriced mixed breed. Poodles have never expressed the dominant Merle pattern, normally found in herding breeds.
2) Anyone who sells a puppy with the Merle pattern, and try’s to pass it off as purebred, is not being entirely honest. Something to think about when you are looking for a breeder is normally honesty. If the individual is breeding for this colour, do not expect them to do proper testing, pedigree research, or care for much more than the pocketbook. I am aware of some “papers” hung, as the registration system is reliant on honesty and self reporting. You can come to your own conclusions.
3) Merle, while an attractive pattern to some, it is fraught with associated health risks to individuals with even one copy of the gene. Breeds that normally have this gene advise great caution, as to breeding advice. Unilateral deafness at 36% is indeed significant where the colour goes near the ears. The blue trait of this mutation is associated with eye problems.
“In both heterozygous ( genotype Mm) and homozygous (genotype MM) merle dogs eze and ear abnormalities have been observed, which included deafness, increased intraocular pressure, bad reflection ability (ametropia) and coloboma ( a hole in one of structures of the eye). Absence of pigment affects also hairs in the inner ear, causing complete deafness. A research proved a deafness prevalence of 54.6% in double merles and 36.8% in single merles.”
4) In the hands of unscrupulous breeders, wanting more coloured pups to sell, Merle to Merle breedings are done. This can cause the pup to have 2 copies of the dominant Merle gene, causing a number of problems. “Blue and partially blue eyes are typically seen with merle, and merle dogs often have a wide range of auditory and ophthalmologic defects. Dogs with 2 copies of merle (called double merle) are primarily white and can have multiple abnormalities of skeletal, cardiac and reproductive systems, thus breedings between 2 merle dogs are discouraged to avoid producing double merle offspring. “ https://www.vgl.ucdavis.edu/services/dog/Merle.php
5) In Poodles specifically, there is a recessive e( White, apricot, Red) gene. In multicolour(parti), the ticking pattern is present. Both these colours can mask or or disable the Merle pattern. This along with the truncated cryptic Merle gene, which can mutate back to the full Merle gene, makes tracking the gene difficult over generations without colour testing.
6 )The most common breed used to bring the colour pattern is Australian Shepherds. This breed has its own health risks to bring to the table. The most worrisome is the MDR1 gene. This gene is called the multi drug resistance gene, and can cause a dog with this gene to have severe and even fatal reactions to common medications. Approximately 50% of the Australian Shepherds carry this gene. They also suffer greatly from allergies and epilepsy. http://www.asca.org/.../health-and.../diseases-and-defects/
7) The MDR1 gene can also show itself as atypical addisons for animals with two copies of the gene.
“There is evidence that homozygous dogs have continuous suppression of the hypothalamic-pituitary axis. According to Dr. Mealey, such “atypical Addisonian” dogs require exogenous corticosteroid supplementation when stressed or ill.”
8)-Many of the breeds that have the Merle pattern need to be tested for collie eye anomaly. It can vary in degree, but is a cause of blindness in these breeds. Some breeds have a large population of carriers and affected. https://www.optigen.com/opt9_test_cea_ch.html
9)For those that think mixed breeds are healthier. While purebreds have breed specific ailments, overall the results show that there is no advantage. This population includes purebreds from both good and bad breeders. Those from tested parents, are more likely to fare better.