The Golden Retriever is affected by a skin disease of genetic origin, called ichthyosis. This dermatosis is very common in Europe and the United States with approximately 30% of dogs developing more or less marked symptoms. Keep an eye on the embedded fully ticks on dogs that are extremely hazardous to the animal. Once you find them on your pets, you must remove them to keep them healthy by using a tick remover for cats.
Clinical signs
The clinical signs appear in dogs aged 1 to 18 months and will persist throughout the life of the animal.
Symptoms are characterized by numerous large, whitish or blackish scales, mainly on the trunk and belly. This dandruff gives a dirty and scaly appearance to the skin; this one is dry, rough often hyper-pigmented, and gives to the touch a sensation of “sandpaper”.
The treatments used are mainly based on increased hygiene measures (brushing, shampoos and emollients) and on a diet enriched with fatty acids. This work opens the way not only to a better understanding of the disease itself but. Also to a better knowledge of the role of this enzyme and the functioning of the skin barrier.
Causes
The research was carried out by the CNRS-University of Rennes 1 Dog Genetics team (Dr. Catherine Andre & collaborators) within the Institute of Genetics and Development of Rennes UMR6061 in Rennes, by Drs Eric Guaguere (Saint-Bernard 59160 Lomme), Emmanuel Bensignor (35510 Cesson-Sevigne), Jacques Fontaine (Brussels, Belgium), and their partners (the LAPVSO and ANTAGENE veterinary laboratories) led to the identification of the mutation responsible for ichthyosis in the Golden Retriever and to the validation of the genetic test. To learn more about ichthyosis: Canine genetics
The pedigree study in the Golden Retriever suggests a genetic disease with the autosomal recessive transmission, linked to the absence of degradation of the retention ichthyosis, similar to vulgar and lamellar ichthyosis in humans.
Scientists progress
It is thanks to Golden Retrievers that French researchers have managed to trace the trail of a rare congenital skin disease that affects some babies from birth
Ichthyoses include a heterogeneous set of genetic dermatoses, characterized by abnormal corneogenesis (or keratinization) resulting in an abnormal accumulation of scales on the surface of the skin (scales taking the form of scales of fish).
They result from the consequences of a defect in one or more steps involved in stratum corneum differentiation and are mostly monogenic in humans. They usually appear in the first weeks or months after birth and will persist throughout life.
While autosomal ichthyosis Vulgaris is a common disease of moderate severity in humans, other forms are rarer and more serious, such as Autosomal Recessive Congenital Ichthyosis (ARCI in English ICRA, in French) as harlequin ichthyosis.
The discovery of new genes in dogs represents an opportunity to identify new genes in human ichthyosis.
Given the difficulty of bringing together enough human families affected by the same clinical entity, the teams of Catherine André (CNRS-University of Rennes, France) and Judith Fischer (CEA of Evry, in France, and Clinical University of Freiburg, Germany) 7 became interested in the Golden Retriever. Like any pure canine breed, the Golden Retriever represents a group of genetically similar animals, descending only from a few common ancestors. Inbreeding results in desired characteristics and qualities in dogs, but can result in the unintended selection of genetic diseases.
This work is the culmination of close collaboration between researchers, breeders. Dog owners, attending veterinarians, and veterinarians specializing in dermatology 2, 5, 6, and 7.
Genetic test
The discovery of the PNPLA1 gene in the Golden Retriever gave rise to a patent application. On behalf of the CNRS and the University of Rennes 1. The diagnosis and screening for ichthyosis in the Golden Retriever, to help breeders better manage their breeding by knowingly choosing the mattings to carry out or avoid. This disease spread rapidly in the breed in the 1980s, following the use of affected dogs for breeding.
Affected dogs develop dermatological symptoms from an early age that will persist for life:
Whitish or pigmented scaling, on the trunk and belly, gives the skin a dirty, scaly, dry. And rough appearance, like “sandpaper”.
The coat, which may mask these scales, is dull and dirty-looking. This work opens the way not only to a better understanding of the disease itself but. Also to a better knowledge of the role of this enzyme and the functioning of the skin barrier.
The dermatosis, which is transmitted according to an autosomal recessive mode, evolves variably. Some dogs present minor forms, while in other cases, the disease tends to worsen during growth.
Bacterial, fungal, or parasitic complications may occur.
This dermatosis is currently underdiagnosed and remains difficult to spot by breeders, especially in dogs with a discreet form.
Diagnostic
The genetic test, easy to implement, allows early detection of the disease. And the early implementation of regular dermatological care to avoid infectious complications. This test also makes it possible to specify the differential diagnosis. In particular atopic dermatitis, and allows the breeder to adapt the mattings between. His breeding animals to avoid giving birth to affected puppies and to reduce the incidence of this disease.
This work is remarkable in more ways than one.
It illustrates how fruitful and important collaboration can be:
- Between breeders, dog owners, and veterinarians whether they are practitioners, dermatologists, or pathologists
- Between veterinary medicine and human medicine
It shows how the study of spontaneous disease in the dog. Can serve both humans and the dog itself by allowing for the first discovery. Of new genetic causes of human diseases and the second life-saving genetic screening. For better management of their breeding.
By allowing the discovery of a new gene involved in a human and canine genetic disease. This work opens the way not only to a better understanding of the disease itself but. Also to a better knowledge of the role of this enzyme and the functioning of the skin barrier.
Catherine André’s team is currently pursuing its research on other canine diseases. Which could lead to beneficial genetic research for humans.
Other mutations identified in dogs have already led to gene therapies for eye diseases. Such as genetic disorders of the retina. This work opens the way not only to a better understanding of the disease itself but. Also to a better knowledge of the role of this enzyme and the functioning of the skin barrier.
So, if you know or suspect other breeds affected, do not hesitate to inform them and send them:
- Blood samples (5 ml on EDTA tube) from dogs with ichthyosis. As well as from older non-affected dogs of the same breeds (which serve as controls)
- Photocopy of the pedigree (if available)
- Photocopy of clinical results or histological analysis
