Health InformationCerebellar Ataxia
1998, hereditary condition called Cerebellar Ataxia (CA) was acknowledged in the Spinone Italiano, with the first suspect cases appearing in 1990. This disease cannot be treated, and of the puppies affected, none has survived past the age of 12 months. Cerebellar Ataxia is not "self-limiting."It is a very real problem that can only be resolved by never breeding from nown CA lines. It has been shown that the mode of inheritance of CA is a simple recessive gene that can be traced to a single dog, Trusco Dell Angelo Del Summano Del Gaesten, imported to Great Britain from Italy.If both sire and dam carry the CA gene, affected puppies maybe born and will die. While death by this disease is heartbreaking, It is the surviving pups that present a threat to the Spinone Italiano as a breed. 50% of these puppies will be carriers of the lethal gene, and each pup from each of their litters in turn will have a 50/50 chance of being a carrier. There is no genetic test for the CA gene, and no way of determining which of these descendants of Trusco is a carrier until it is bred to another Trusco descendant and CA affected puppies are produced. The Spinone Club of America, the AKC parent club of the Spinone Italiano, is committed to the health of our dogs. We do not find ANY risk of perpetuating the CA gene, and thus risking producing CA affected puppies, acceptable. SCOA breeders must OFA certify Spinone for hip dysplasia prior to breeding, CERF eyes, and ensure that no Spinoni are bred from the known Cerebellar Ataxia lines. Before you buy or breed a Spinone, it is important to know: Self limiting, meaning the dogs that have CA die before they can be bred. The dogs that are affected by CA do die very young. Those dogs will have littermates that are carriers of the gene while not being affected by it. The problem with the self-limiting concept is not the affected dogs, but the carrier dogs…….the dogs that appear healthy but carry the CA gene. When a known carrier is bred to a clear line, fifty percent of the puppies will be carriers. We have no way of knowing which ones are clear and which ones are carriers. Those carrier puppies will never be affected, meaning they will never succumb to CA. However, they can pass the carrier genes to their own puppies. The more CA lines are bred, the more possible carriers we put into the gene/breeding pool. We've never had a KNOWN affected CA puppy in the United States, but there have been suspect deaths of puppies from affected lines. If we continue breeding CA carrier lines it is only a matter of time before these carriers will start to meet up. That's what the SCOA is afraid of. Once those carriers start meeting up, we will have CA affected puppies in the United States. CA is not political, it is a disease and a real problem: All one has to do is look at other breeds to realize CA is a serious problem. There are many breeds that have serious genetic health problems that would not exist if certain dogs had not been bred. Boxers have a life threatening heart defect that can be traced back to a very popular stud dog, much like CA can be traced back to one dog. Unfortunately, this Boxer had been bred many times before anyone realized there was a problem. Now the breed is inundated with it. Doberman Pinschers also have genetic heart problem. Twenty years ago breeders insisted that there was no proof it was genetic and continued to breed dogs whose parents had died of the disease. Now there are no lines of Dobies that are clear of the disease. Breeding CA lines is even worse than what happened with Boxers and Doberman Pinschers. We have a much smaller gene pool and we know the dogs that shouldn't be bred until a genetic test becomes available. The problem is breeders who choose to pass on the carrier genes their dogs possess.Knowing what we know has happened in other breeds and knowing that some breeders continue to breed possible carriers, is the problem real or political? The puppy does NOT only have a 2% chance of being a carrier. None of the CA line dogs currently being bred in the United States are from lines that have been cleared by pedigree research in Great Britain. Since none of these lines have been cleared, there is no way to know how likely it is that any particular dog is a carrier. We also need to look at the way statistics and percentages work in breeding dogs when you have a simple recessive gene. When a CA carrier is bred to a clear dog, the puppies have a 50/50 chance of being carriers. If the CA clear puppies are bred to clear line, then there is a 0% chance of carriers being produced from that line of dogs. But if one of the carrier puppies produced is bred to clear lines, then ALL of the puppies produced still have a 50/50 chance of being carriers. The chances never reduce. It doesn't suddenly become 25%, then 12%, then 6%, then 2% with subsequent generations. A great great great great granddaughter of a carrier still has the same 50/50 chance of being a carrier. Nobody knows which descendants of CA carriers are carriers and which are not until they risk breeding dying puppies to find out. This is unnecessary and unacceptable to SCOA.We all love our dogs, but breeders who love the breed make responsible breeding choices. Great News, The CA AHT research in England has descovered the gene DIRECTLY related to CA (The AHT stands for the Animal Health Trust, who is involved with the research.) Thank you! Katherine Cooker Cerebellar ataxia in the Italian Spinone Cerebellar ataxia (CA) in the Italian Spinone is a serious neurological disease. In affected dogs the cerebellum, which is the part of the brain responsible for the co-ordination of motor movement in the body, becomes diseased. Affected dogs are born normal, but clinical signs, which include the development of an unsteady gait, loss of co-ordination and poor balance usually appear in the first weeks or months of life. The disease is progressive; symptoms worsen during the first year of the dog’s life such that most dogs are euthanased before they are 1 year old. There is no treatment for the disease, which has an autosomal recessive mode of inheritance. The genetic mutation that is responsible for the condition probably occurred spontaneously in a single dog but once in the population has been inherited from generation to generation like any other gene. The disorder shows an autosomal recessive mode of inheritance: a dog has to inherit two copies of the defective gene (one from each parent) for it to be affected by the disease. Individuals with one copy of the defective gene and one copy of the normal gene are called carriers and show no clinical signs but can pass the defective gene onto their offspring. When two apparently healthy carriers are crossed, 25% (on average) of the offspring will be affected by the disease, 25% will be clear and the remaining 50% will be carriers. The region of the genome that contains the causal mutation has recently been identified at the Animal Health Trust. Using the information gained from this research, we have developed a linkage-based DNA test for the disease which we estimate will give an accurate result for between 95% and 98% of dogs tested. This test will detect those dogs which are carriers of the CA mutation, and those that are clear of the mutation. Breeders will be sent results identifying their dog as belonging to one of three categories: CLEAR: This DNA test detects markers close to the gene responsible for CA - our research has indicated that the test is 95-98% accurate. CLEAR dogs have 2 copies of the normal gene and will neither develop cerebellar ataxia, nor pass a cerebellar ataxia gene to their offspring. CARRIER: This DNA test detects markers close to the gene responsible for CA - our research has indicated that the test is 95-98% accurate. CARRIER dogs have one copy of the normal gene and one copy of the mutant gene that causes cerebellar ataxia. They will not develop cerebellar ataxia but will, if bred from, pass on the cerebellar ataxia gene to, on average, 50% of its offspring. AFFECTED: This DNA test detects markers close to the gene responsible for CA - our research has indicated that the test is 95-98% accurate. AFFECTED dogs have 2 copies of the mutant gene that causes cerebellar ataxia and will develop the disease. Carriers can still be bred to tested clear dogs. On average, 50% of such a litter will be clear and 50% carriers; there can be no affecteds produced from such a mating. Pups which will be used for breeding can themselves be DNA tested to determine whether they are clear or carrier. Samples submitted should be cheek swabs (a non-invasive sampling method) obtainable from the Animal Health Trust. Samples should be sent together with a completed DNA Testing form and payment for each sample to Genetic Services, Animal Health Trust, Lanwades Park, Kentford, Newmarket, Suffolk CB8 7UU. Kits for taking cheek swabs are available by phoning 01638 555621 or via e-mail to [email protected]. The price of the test is £56, which includes both VAT and the cost of the sampling kit. Further information can be obtained by e-mailing[email protected] |