Lysosomal Storage Disease in Lagotto Romagnolo: Causes & Testing

Lagotto Romagnolo puppies can be affected by a serious hereditary condition called lysosomal storage disease (LSD), sometimes referred to as Lagotto storage disease. This inherited disorder impairs the dog’s metabolic functions due to a deficiency of enzymes needed to digest and eliminate waste products.

Without these enzymes, substances that would normally be expelled accumulate abnormally in the dog’s tissue cells, especially in the nervous system. This buildup causes cells to swell or die, leading to progressive neurological damage.

The disease is ultimately fatal and currently has no cure. Although lysosomal storage diseases exist in humans and other animals, the variant affecting Lagotto Romagnolos is specific to the breed and relatively well researched.

LSD is not contagious; a dog must inherit two copies of the mutated gene (one from each parent) to develop the disease. Dogs with a single mutated gene copy are carriers but appear healthy.

To help responsible breeders, The Kennel Club has established a screening scheme. This allows testing breeding dogs for the LSD genetic marker to inform safe breeding decisions and reduce disease prevalence.

Understanding Lysosomal Storage Disease in Lagotto Romagnolos

LSD is caused by a mutation in the ATG4D gene that controls a vital enzyme involved in lysosomal recycling — the process cells use to break down and dispose of unnecessary materials. Dysfunction in this system causes harmful waste to accumulate, mostly impacting the nervous system’s cells.

Symptoms typically appear between four months and four years old, varying in severity and progression. Early signs often include neurological issues such as loss of coordination (ataxia), episodic involuntary eye movements (nystagmus), clumsiness, unusual restlessness, changes in mood including depression, and uncharacteristic aggression. Sadly, symptoms worsen over time, severely impacting quality of life.

Diagnosis relies on genetic testing since clinical symptoms can overlap with other neurological disorders in the breed.

Which Lagotto Romagnolo Dogs Are Affected?

Any purebred Lagotto Romagnolo can inherit the mutated genes causing LSD. The disease manifests only if the dog inherits two copies of the mutation, one from each parent, making it an autosomal recessive condition.

Cross-breeds carrying only one copy of the mutated gene do not develop LSD thanks to hybrid vigour, although they may carry and pass on the gene to offspring.

How LSD Is Inherited: The Genetics Explained

Lysosomal storage disease in Lagotto Romagnolos is an autosomal recessive genetic disorder. This means a dog’s status falls into one of three categories based on gene inheritance:

• Clear: inherits no mutated genes, cannot develop or pass on LSD.
• Carrier: inherits one mutated gene, usually healthy but can pass mutation to offspring.
• Affected: inherits two mutated genes, will develop LSD and suffer progressive neurological symptoms.

Breeding outcomes vary depending on the parents’ genetic status:

• Two clear dogs produce only clear puppies.
• Two affected dogs produce only affected puppies.
• Two carriers produce roughly 25% clear, 50% carriers, and 25% affected puppies.
• A clear and a carrier produce 50% clear and 50% carriers.
• A clear and an affected dog produce 100% carriers.
• A carrier and an affected dog produce approximately 50% carriers and 50% affected.

Testing for Lysosomal Storage Disease in Your Lagotto Romagnolo

Genetic testing is the cornerstone of responsible breeding to prevent LSD. Prospective breeders are strongly encouraged to know their dogs’ genotype before breeding to avoid producing affected puppies.

Testing involves submitting a DNA sample, typically collected by your vet through a cheek swab or blood sample, to a laboratory approved by The Kennel Club. Test results will confirm whether the dog is clear, carrier, or affected.

Using this knowledge, breeders can make responsible breeding decisions, such as avoiding carrier-to-carrier matings, thereby reducing LSD incidence in the breed while maintaining genetic diversity.

Responsible Breeding and Care

The availability of a genetic test for LSD supports owners and breeders in making informed choices that promote the health and welfare of Lagotto Romagnolos. Breeders adhering to these protocols contribute significantly to reducing this devastating disease.

If you are considering getting a Lagotto Romagnolo puppy, always seek out reputable breeders who perform genetic health testing to ensure you receive a healthy puppy and preserve the breed’s long-term wellbeing.