Dog Diseases Database
Every hereditary and common canine condition — with tests, affected body regions, and the breeds where each shows up most.
Filters
- SevereGeneral / metabolicAutosomal recessive
Glycogen storage disease IV(GSD IV)
This is an inherited metabolic disorder where a deficiency in the glycogen branching enzyme prevents the body from properly storing and using sugar. Instead, abnormal glycogen molecules build up inside vital organs, particularly the liver, muscles, and nervous system, causing progressive and irreversible tissue damage.
View details - SevereHead / nervous systemAutosomal recessive
GM2 Gangliosidosis, type II (Sandhoff disease or variant 0)(GM2)
This is an inherited lysosomal storage disease affecting the nervous system, caused by a lack of vital enzymes. Without these enzymes, fatty substances called gangliosides build up to toxic levels inside the cells. This accumulation progressively damages the dog's brain and nerve cells.
View details - SevereHead / nervous systemAutosomal recessive
Granule cell type cerebellar hypoplasia(GCCH)
This is an extremely rare developmental disorder of the brain, specifically affecting the cerebellum, which controls balance and coordination. In this condition, a specific layer of brain cells called the granule cell layer fails to develop properly. Because this part of the brain is underdeveloped, the dog cannot coordinate its movements normally.
Tested via: Radiograph, DNA testView details - MildGeneral / metabolicAutosomal recessive
GST-theta enzyme activity, GSTT1-like-related(GSTT1)
This genetic variation reduces the activity of the GST-theta enzyme, which is part of the liver's metabolic system. This enzyme is responsible for breaking down and neutralizing environmental toxins and certain medications. Without fully functioning enzymes, the dog's body may process these substances more slowly than normal.
View details - HighHead / nervous systemUnknown
Guillain-Barré-like polyradiculoneuropathy(APN)
This condition, also known as Acute Canine Polyradiculoneuritis (ACP), is an acute, immune-mediated inflammation of the peripheral nervous system. The dog's immune system mistakenly attacks the nerves and nerve roots that connect the spinal cord to the muscles. This disrupts the electrical signals needed for muscle control, leading to weakness or paralysis.
View details - SevereHead / nervous systemAutosomal recessive
HACE1-related ataxia
HACE1-related ataxia is an inherited neurological disorder caused by a genetic mutation that leads to progressive damage in the cerebellum, which is the part of the brain responsible for coordinating movement. Without a properly functioning cerebellum, the brain cannot accurately control the muscles, leading to a loss of voluntary motor coordination.
Tested via: DNA testView details - MildSkin & coatAutosomal dominant
Harlequin coat color(H)
The harlequin coat pattern is a genetic trait that modifies the merle gene, affecting the pigment-producing cells in a dog's skin and hair. This autosomal dominant modifier causes some of the diluted grey areas of a merle coat to become white, leaving irregular, torn black patches. While viable puppies inherit only one copy of this gene, inheriting two copies is lethal during embryonic development.
View details - ModerateGeneral / metabolicComplex
Heat tolerance
Heat tolerance is a metabolic and homeostatic trait that determines how effectively a dog's body regulates its internal core temperature in warm environments. When this regulation fails, the metabolic system cannot balance heat production with heat loss, often involving the respiratory and cardiovascular systems. This complex genetic trait influences how efficiently a dog can cool itself down to prevent overheating.
View details - MildGeneral / metabolicComplex
Height, HMGA2-associated body-size variation
This is a natural genetic variation rather than a disease, affecting the skeletal system and overall body development. The HMGA2 gene plays a key role in regulating cell growth and division during development, which directly influences a dog's final skeletal height at the shoulders. Because this is a normal physical trait, it does not cause any underlying organ dysfunction or health issues.
View details - MildGeneral / metabolicComplex
Height, IGF1-AS-associated body-size variation(IGF1-AS)
This genetic variation affects a non-coding antisense RNA molecule (IGF1-AS) that regulates the expression of Insulin-like Growth Factor 1, a key hormone controlling skeletal growth. This variation influences how much of the hormone is produced, directly impacting the development of the skeletal and muscular systems. It is a natural genetic regulator of physical stature rather than a disease or medical disorder.
View details - MildGeneral / metabolicComplex
Height, IGF2BP2-associated body-size variation
This genetic variation affects the IGF2BP2 gene, which plays a role in regulating growth and skeletal development. It is a normal genetic trait that influences a dog's overall skeletal size and height rather than a disease or medical condition. The gene helps control how cells grow and divide during development, affecting the final stature of the dog's skeletal system.
View details - HighGeneral / metabolicUnknown
Hemimelia
Hemimelia is a congenital skeletal deformity where a portion of a limb bone, such as the radius in the front leg or the tibia in the hind leg, is incompletely formed or entirely missing. This developmental error occurs in the womb and affects the musculoskeletal system, leading to severe shortening or distortion of the affected leg. Because the bone structure is incomplete, the normal joints and muscles of the limb cannot function properly.
View details - HighGeneral / metabolicComplex
Hemochromatosis
Hemochromatosis is a metabolic disorder where the body absorbs excessive iron from food, leading to a toxic buildup in vital organs, particularly the liver. Over time, this excess iron damages cells and impairs organ function. Diagnosis is confirmed using a specialized blood test called an iron panel (Eisen-Panel) alongside a liver biopsy (Leberbiopsie) to evaluate iron levels in the liver cells.
View details - SevereGeneral / metabolicComplex
Hemolytic uremic syndrome(HUS)
Hemolytic uremic syndrome (HUS), also known as Alabama Rot or Cutaneous and Renal Glomerular Vasculopathy (CRGV), is a severe condition that causes damage to the small blood vessels, primarily affecting the kidneys and skin. This damage leads to the premature destruction of red blood cells and a rapid drop in platelets, which are the cells responsible for blood clotting. The resulting blockages in the tiny blood vessels of the kidneys can quickly lead to acute kidney failure.
View details - SevereGeneral / metabolicUnknown
Hemophagocytic syndrome(HLH)
Hemophagocytic syndrome is a severe disorder of the immune system where the body's defense cells abnormally activate and begin destroying its own healthy blood cells, including red blood cells, white blood cells, and platelets. This destructive process primarily occurs in the spleen, bone marrow, and liver, leading to a critical shortage of vital blood components.
View details - SevereHead / nervous systemAutosomal recessive
Hereditary sensory and autonomic neuropathy, SCN9A-related(HSAN)
This is a severe, inherited nervous system disorder caused by a genetic mutation in the SCN9A gene. It disrupts the normal function of sensory nerves, which are the pathways responsible for transmitting signals like pain and temperature to the brain. Without these signals, affected dogs cannot feel pain or heat, leaving them unable to protect themselves from injury.
View details - ModerateGeneral / metabolicUnknown
Heterotopic ossification
Heterotopic ossification is a condition where true bone tissue abnormally develops inside soft tissues like muscles, tendons, or ligaments where it does not belong. This misplaced bone growth occurs within the musculoskeletal system, typically triggered by trauma, surgery, or deep tissue injury. Over time, these hard deposits can restrict the normal movement of the surrounding joints and muscles.
View details - ModerateGeneral / metabolicComplex
Hiatal hernia
A hiatal hernia is a physical defect in the diaphragm, which is the muscular barrier separating the chest cavity from the abdomen. This opening allows the upper portion of the stomach to slide forward into the chest, disrupting the normal passage of food and causing acid reflux.
View details - MildGeneral / metabolicAutosomal recessive
High-activity sodium-potassium-ATPase
This genetic condition affects the red blood cells by causing overactivity in the sodium-potassium pump, which is the mechanism that regulates salt and water balance within the cells. This imbalance can cause the red blood cells to become misshapen into cup-like forms called stomatocytes, which can shorten their lifespan. It is typically identified through routine blood tests that show these abnormal cells and altered electrolyte levels.
View details - SevereGeneral / metabolicUnknown
Hodgkin's lymphoma
Hodgkin's-like lymphoma is an extremely rare type of cancer affecting the lymphatic system, which is a key part of the dog's immune network. In this condition, abnormal white blood cells multiply uncontrollably and accumulate within the lymph nodes, disrupting their normal function. Unlike more common canine lymphomas, this specific variant typically begins in a single lymph node or a localized group of nodes.
View details - MildHead / nervous systemUnknown
Horner syndrome
Horner's syndrome is a neurological condition resulting from a disruption in the sympathetic nervous system, which controls involuntary functions like pupil dilation and facial muscle tone. It is not a disease itself, but rather a collection of symptoms that can be triggered by middle ear infections, neck trauma, or tumors along the nerve pathway. In many cases, the condition is classified as idiopathic, meaning no clear underlying cause can be identified.
View details - SevereHead / nervous systemUnknown
Hydranencephaly
Hydranencephaly is a severe brain malformation affecting the central nervous system where the cerebral hemispheres, which are the main parts of the brain responsible for thought and movement, fail to develop. Instead of normal brain tissue, the space inside the skull is filled with cerebrospinal fluid. This is a congenital condition, meaning the puppy is born with the defect.
View details - HighHead / nervous systemComplex
Hydromyelia
Hydromyelia is an abnormal widening of the central canal within the spinal cord, which is the fluid-filled tube running through the center of the spine. This occurs when cerebrospinal fluid, the protective liquid surrounding the brain and spinal cord, builds up and puts pressure on the surrounding nerve tissue. Over time, this pressure can cause progressive damage to the nervous system.
View details - SevereGeneral / metabolicUnknown
Hydrops fetalis
Hydrops fetalis is a severe developmental condition where abnormal amounts of fluid build up within a puppy's tissues and body cavities before birth. This widespread fluid accumulation affects multiple organ systems, preventing normal development in the womb. Because there is currently no genetic test available, the exact underlying cause and inheritance pattern remain unknown.
View details - HighGeneral / metabolicComplex
Hyperbilirubinemia
Hyperbilirubinemia is a metabolic condition characterized by an excess of bilirubin, a yellow pigment formed during the normal breakdown of red blood cells, in the bloodstream. This buildup typically points to an underlying issue with the liver, gallbladder, or bile ducts, which normally process and excrete this pigment. Because it is a generic metabolic phenotype with complex inheritance, it can stem from various genetic or environmental causes affecting these organ systems.
View details
Why HonestDog?
What makes HonestDog different from other platforms
Full transparency
We lay out what we have: who the breeder is, how they work, and any health records they've uploaded. So you can judge for yourself.
Responsible breeding, assured
Every breeder on HonestDog has their identity and documents checked before their profile goes live. Health records they upload are shown on the profile, so you can see exactly what has been tested.
Trust and verification
We verify breeders and buyers alike, so every conversation happens on solid ground. It's a new standard of trust in dog breeding.
Less hassle, more time
We've already checked the breeders' documents and gathered the details, so you can skip the endless research and focus on finding the right puppy for your family.
Our Mission

We connect dog lovers with responsible breeders and shelters to ensure every dog finds the perfect home.
Founded by dog enthusiasts, our platform focuses on ethical dog breeding and adoption.
Why HonestDog?
We connect you with vetted breeders and shelters so you can find your — your new companion — with confidence.
Vetted Partners
Only verified breeders and shelters — for a safe start.
Highest Standards
Every animal's health and wellbeing is our top priority.
Guides & Resources
Guides, checklists, and breed profiles — so you can make a well-informed decision.