No sexual predilection is observed because the deficiency of glycogen synthetase activity is inherited as an autosomal recessive trait.

The major morbidity is a risk of fasting hypoglycemia, which can vary in severity and frequency. Major long-term concerns include growth delay, osteopenia, and neurologic damage resulting in developmental delay, intellectual deficits, and personality changes.

Fucosidosis is an extremely rare disorder first described in 1962 in two Italian siblings who showed progressive intellectual disability and neurological deterioration. The disease itself is extremely rare (less than 100 documented cases) only affecting 1:2,000,000, with most cases being occurring in Italy, Cuba, and the southwest U.S. The disease has three different types. Type 1 and 2 are considered severe, and Type 3 being a mild disease. Symptoms are highly variable with mild cases being able to live to within the third or fourth decade. Type 1 and 2 are both linked with mental retardation. Severe cases can develop life-threatening complications early in childhood.

Because the major accumulating glycoconjugate in fucosidosis patients is the blood group H-antigen, it is intriguing to speculate, but the evidence is not clear at this time, that blood type may affect the course of the disease.

Citrullinemia type I (CTLN1), also known as arginosuccinate synthetase deficiency, is a rare disease caused by a deficiency in argininosuccinate synthetase, an enzyme involved in excreting excess nitrogen from the body. There are mild and severe forms of the disease, which is one of the urea cycle disorders.

Overall, according to a study in British Columbia, approximately 2.3 children per 100,000 births (1 in 43,000) have some form of glycogen storage disease. In the United States, they are estimated to occur in 1 per 20,000–25,000 births. Dutch incidence rate is estimated to be 1 per 40,000 births.

Arginosuccinate synthetase is an enzyme in the urea cycle, which removes excess ammonia from the body. When it is deficient, either fully or partially, ammonia can build up and cause the signs and symptoms of CTLN1.

Citrullinemia is an autosomal recessive urea cycle disorder that causes ammonia and other toxic substances to accumulate in the blood. Since the substances also accumulate in the urine, the disorder can also be called citrullinuria.

Two forms of citrullinemia have been described, both having different signs and symptoms, and are caused by mutations in different genes. Citrullinemia belongs to a class of genetic diseases called urea cycle disorders. The urea cycle is a sequence of chemical reactions taking place in the liver. These reactions process excess nitrogen, generated when protein is used for energy by the body, to make urea, which is excreted by the kidneys.

There are multiple treatment methods. Low protein diets, are intended to minimize production of ammonia. Arginine, sodium benzoate and sodium phenylacetate help to remove ammonia from the blood. Dialysis may be used to remove ammonia from the blood when it reaches critical levels.

In some cases, liver transplant has been successful.

Type 1 tyrosinemia, also known as hepatorenal tyrosinemia or tyrosinosis, is the most severe form of tyrosinemia, a buildup of too much of the amino acid tyrosine in the blood and tissues due to an inability to metabolize it. It is caused by a deficiency of the enzyme fumarylacetoacetate hydrolase.

Galactose epimerase deficiency, also known as GALE deficiency, Galactosemia III and UDP-galactose-4-epimerase deficiency, is a rare, autosomal recessive form of galactosemia associated with a deficiency of the enzyme "galactose epimerase".

Mutations in the FAH, TAT, or HPD gene cause a decrease in the activity of one of the enzymes in the breakdown of tyrosine.

As a result, tyrosine and its byproducts accumulate to toxic levels, which can cause damage and death to cells in the liver, kidneys, nervous system, and other organs.

Canine fucosidosis is found in the English Springer Spaniel.

Typically affecting dogs between 18 months and four years, symptoms include:

- Loss of learned behavior

- Change in temperament

- Blindness

- Loss of balance

- Deafness

- Weight loss

- From the onset, disease progress is quick and fatal.

Just like the human version, canine fucosidosis is a recessive disorder and two copies of the gene must be present, one from each parent, in order to show symptoms of the disease.

Tyrosinemia or tyrosinaemia is an error of metabolism, usually inborn, in which the body cannot effectively break down the amino acid tyrosine. Symptoms include liver and kidney disturbances and intellectual disability. Untreated, tyrosinemia can be fatal.Most inborn forms of tyrosinemia produce hypertyrosinemia (high levels of tyrosine).

Individuals presenting with Type III galactosemia must consume a lactose- and galactose-restricted diet devoid of dairy products and mucilaginous plants. Dietary restriction is the only current treatment available for GALE deficiency. As glycoprotein and glycolipid metabolism generate endogenous galactose, however, Type III galactosemia may not be resolved solely through dietary restriction.

Treatment is depended on the type of glycogen storage disease. E.g. GSD I is typically treated with frequent small meals of carbohydrates and cornstarch to prevent low blood sugar, while other treatments may include allopurinol and human granulocyte colony stimulating factor.

Niemann–Pick Type A, the most common type, occurs in infants and is characterized by jaundice, an enlarged liver, failure to thrive, progressive deterioration of the nervous system and profound brain damage. Children affected by Niemann Pick Type A rarely live beyond 18 months. Niemann–Pick Type A occurs more frequently among individuals of Ashkenazi (eastern and central European) Jewish descent than in other ethnicities. The incidence within the Ashkenazi population is approximately 1 in 40,000 people. The incidence for other populations is 1 in 250,000 people.

Type 1 tyrosinemia is inherited in an autosomal recessive pattern. Worldwide, type I tyrosinemia affects about 1 person in 100,000. This type of tyrosinemia is much more common in Quebec, Canada. The overall incidence in Quebec is about 1 in 16,000 individuals. In the Saguenay-Lac-Saint-Jean region of Quebec, type 1 tyrosinemia affects 1 person in 1,846. The carrier rate has been estimated to be between 1 in 20 and 1 in 31.

Niemann–Pick Type B involves an enlarged liver and spleen hepatosplenomegaly, growth retardation, and problems with lung function including frequent lung infections. Other signs include blood abnormalities such as abnormal cholesterol and lipid levels, and low numbers of blood cells involved in clotting (platelets). The brain is not affected in Type B and the disease often presents in the pre-teen years.

The disease is typically progressive, leading to fulminant liver failure and death in childhood, in the absence of liver transplantation. Hepatocellular carcinoma may develop in PFIC-2 at a very early age; even toddlers have been affected.

Lysosomal storage diseases (LSDs; ) are a group of about 50 rare inherited metabolic disorders that result from defects in lysosomal function. Lysosomes are sacs of enzymes within cells that digest large molecules and pass the fragments on to other parts of the cell for recycling. This process requires several critical enzymes. If one of these enzymes is defective, because of a mutation, the large molecules accumulate within the cell, eventually killing it.

Lysosomal storage disorders are caused by lysosomal dysfunction usually as a consequence of deficiency of a single enzyme required for the metabolism of lipids, glycoproteins (sugar-containing proteins), or so-called mucopolysaccharides. Individually, LSDs occur with incidences of less than 1:100,000; however, as a group, the incidence is about 1:5,000 - 1:10,000. Most of these disorders are autosomal recessively inherited such as Niemann–Pick disease, type C, but a few are X-linked recessively inherited, such as Fabry disease and Hunter syndrome (MPS II).

The lysosome is commonly referred to as the cell's recycling center because it processes unwanted material into substances that the cell can use. Lysosomes break down this unwanted matter by enzymes, highly specialized proteins essential for survival. Lysosomal disorders are usually triggered when a particular enzyme exists in too small an amount or is missing altogether. When this happens, substances accumulate in the cell. In other words, when the lysosome does not function normally, excess products destined for breakdown and recycling are stored in the cell.

Like other genetic disorders, individuals inherit lysosomal storage diseases from their parents. Although each disorder results from different gene mutations that translate into a deficiency in enzyme activity, they all share a common biochemical characteristic – all lysosomal disorders originate from an abnormal accumulation of substances inside the lysosome.

LSDs affect mostly children and they often die at a young and unpredictable age, many within a few months or years of birth. Many other children die of this disease following years of suffering from various symptoms of their particular disorder.

The symptoms of LSD vary, depending on the particular disorder and other variables such as the age of onset, and can be mild to severe. They can include developmental delay, movement disorders, seizures, dementia, deafness, and/or blindness. Some people with LSDhave enlarged livers (hepatomegaly) and enlarged spleens (splenomegaly), pulmonary and cardiac problems, and bones that grow abnormally.

Horses with PSSM show fewer clinical signs if their exercise is slowly increased over time (i.e. they are slowly conditioned). Additionally, they are much more likely to develop muscle stiffness and rhabdomyolysis if they are exercised after prolonged stall rest.

Horses generally have fewer clinical signs when asked to perform short bouts of work at maximal activity level (aerobic exercise), although they have difficulty achieving maximal speed and tire faster than unaffected horses. They have more muscle damage when asked to perform lower intensity activity over a longer period of time (aerobic activity), due to an energy deficit in the muscle.

PSSM is most prevalent in American Quarter Horses and their related breeds (Paint horse, Appaloosa, Appendix Quarter Horse), Draft horse breeds (especially Belgian Draft and Percherons), and Warmblood breeds. The Belgian Draft been shown to have a 36% prevalence of PSSM. Other breeds that have been diagnosed with PSSM include the Arabian, Lipizzaner, Morgan, Mustang, Peruvian Paso, Rocky Mountain Horse, Standardbred, Tennessee Walking Horse, Thoroughbred, and National Show Horse. It has been suggested that the GSY1 mutation provided some benefit to hard working animals with poor-quality diets, and is now damaging members of those "thrifty" breeds that are managed with moderate to low levels of work and diets high in non-structural carbohydrates.

PSSM Type 1 (homozygous or heterozygous for the GSY1 mutation) is more common in Quarter Horses and their related breeds, and draft breeds, while PSSM Type 2 (negative for the GSY1 mutation) is more commonly seen in other breeds, including warmbloods. There is no sex predilection to the disease.

Congenital generalized lipodystrophy (also known as Berardinelli–Seip syndrome) is an extremely rare autosomal recessive skin condition, characterized by an extreme scarcity of fat in the subcutaneous tissues. It is a type of lipodystophy disorder where the magnitude of fat loss determines the severity of metabolic complications. Only 250 cases of the condition have been reported, and it is estimated that it occurs in 1 in 10 million people worldwide.

In terms of frequency, is estimated at 2 per 100,000, it has identified in different regions of the world. Some clusters of certain types of autosomal dominant cerebellar ataxia reach a prevalence of 5 per 100,000.