Glycogen storage disease type V, also known as McArdle's disease, is a metabolic disorder, one of the metabolic myopathies, more specifically a muscle glycogen storage disease, caused by a deficiency of myophosphorylase. Its incidence is reported as one in 100,000, roughly the same as glycogen storage disease type I.
A glycogen storage disease is a metabolic disorder caused by a deficiency of an enzyme or transport protein affecting glycogen synthesis, glycogen breakdown, or glucose breakdown, typically in muscles and/or liver cells.
The Norwegian Forest Cat, less commonly referred to as just Norwegian Forest, is a breed of domestic cat originating in Northern Europe. This landrace breed is adapted to a very cold climate, with a top coat of long, glossy hair and a woolly undercoat for insulation. The breed's ancestors may have been a landrace breed of short-haired cats brought to Norway about A.D. 1000 by the Vikings, who may also have brought with them long-haired cats, like those ancestral to the modern Siberian and Turkish Angora.
Phosphoglucomutase is an enzyme that transfers a phosphate group on an α-D-glucose monomer from the 1 to the 6 position in the forward direction or the 6 to the 1 position in the reverse direction.
Glycogen storage disease type II(GSD-II), also called Pompe disease, and formerly known as GSD-IIa or Limb–girdle muscular dystrophy2V, is an autosomal recessive metabolic disorder which damages muscle and nerve cells throughout the body. It is caused by an accumulation of glycogen in the lysosome due to deficiency of the lysosomal acid alpha-glucosidase enzyme (GAA). The inability to breakdown glycogen within the lysosomes of cells leads to progressive muscle weakness throughout the body and affects various body tissues, particularly in the heart, skeletal muscles, liver and the nervous system.
Phosphofructokinase deficiency is a rare muscular metabolic disorder, with an autosomal recessive inheritance pattern. It is characterized as a deficiency in the Phosphofructokinase (PFK) enzyme throughout the body, including the skeletal muscles and red blood cells. Phosphofrucotkinase is an enzyme involved in the glycolytic process. The lack of PFK blocks the completion of the glycolytic pathway. Therefore, all products past the block would be deficient, including Adenosine triphosphate (ATP).
Glycogen storage disease type I is an inherited disease that prevents the liver from properly breaking down stored glycogen, which is necessary to maintain adequate blood sugar levels. GSD I is divided into two main types, GSD Ia and GSD Ib, which differ in cause, presentation, and treatment. There are also possibly rarer subtypes, the translocases for inorganic phosphate or glucose ; however, a recent study suggests that the biochemical assays used to differentiate GSD Ic and GSD Id from GSD Ib are not reliable, and are therefore GSD Ib.
Glycogen-branching enzyme deficiency (GBED) is an inheritable glycogen storage disease affecting American Quarter Horses and American Paint Horses. It leads to abortion, stillbirths, or early death of affected animals. The human form of the disease is known as glycogen storage disease type IV.
The glycogen debranching enzyme, in humans, is the protein encoded by the gene AGL. This enzyme is essential for the breakdown of glycogen, which serves as a store of glucose in the body. It has separate glucosyltransferase and glucosidase activities.
Glycogen storage disease type III (GSD III) is an autosomal recessive metabolic disorder and inborn error of metabolism (specifically of carbohydrates) characterized by a deficiency in glycogen debranching enzymes. It is also known as Cori's disease in honor of the 1947 Nobel laureates Carl Cori and Gerty Cori. Other names include Forbes disease in honor of clinician Gilbert Burnett Forbes (1915–2003), an American physician who further described the features of the disorder, or limit dextrinosis, due to the limit dextrin-like structures in cytosol. Limit dextrin is the remaining polymer produced after hydrolysis of glycogen. Without glycogen debranching enzymes to further convert these branched glycogen polymers to glucose, limit dextrinosis abnormally accumulates in the cytoplasm.
Glycogen storage disease type 0 is a disease characterized by a deficiency in the glycogen synthase enzyme (GSY). Although glycogen synthase deficiency does not result in storage of extra glycogen in the liver, it is often classified as a glycogen storage disease because it is another defect of glycogen storage and can cause similar problems. There are two isoforms (types) of glycogen synthase enzyme; GSY1 in muscle and GSY2 in liver, each with a corresponding form of the disease. Mutations in the liver isoform (GSY2), causes fasting hypoglycemia, high blood ketones, increased free fatty acids and low levels of alanine and lactate. Conversely, feeding in these patients results in hyperglycemia and hyperlactatemia.
1,4-alpha-glucan-branching enzyme, also known as brancher enzyme or glycogen-branching enzyme is an enzyme that in humans is encoded by the GBE1 gene.
Equine polysaccharide storage myopathy is a hereditary glycogen storage disease of horses that causes exertional rhabdomyolysis. It is currently known to affect the following breeds American Quarter Horses, American Paint Horses, Warmbloods, Cobs, Dales Ponies, Thoroughbreds, Arabians, New Forest ponies, and a large number of Heavy horse breeds. While incurable, PSSM can be managed with appropriate diet and exercise. There are currently 2 subtypes, known as Type 1 PSSM and Type 2 PSSM.
Myophosphorylase or glycogen phosphorylase, muscle associated (PYGM) is the muscle isoform of the enzyme glycogen phosphorylase and is encoded by the PYGM gene. This enzyme helps break down glycogen into glucose-1-phosphate, so it can be used within the muscle cell. Mutations in this gene are associated with McArdle disease, a glycogen storage disease of muscle.
Phosphorylase b kinase gamma catalytic chain, testis/liver isoform is an enzyme that in humans is encoded by the PHKG2 gene.
Glycogen storage disease type IX is a hereditary deficiency of glycogen phosphorylase kinase B that affects the liver and skeletal muscle tissue. It is inherited in an X-linked or autosomal recessive manner.
Inborn errors of carbohydrate metabolism are inborn error of metabolism that affect the catabolism and anabolism of carbohydrates.
Metabolic myopathies are myopathies that result from defects in biochemical metabolism that primarily affect muscle. They are generally genetic defects that interfere with the ability to create energy, causing a low ATP reservoir within the muscle cell.
Adult polyglucosan body disease (APBD) is a rare monogenic glycogen storage disorder caused by an inborn error of metabolism. Symptoms can emerge any time after the age of 30. Early symptoms include trouble controlling urination, trouble walking, and lack of sensation in the legs. People eventually develop dementia.
Sengers syndrome is a rare autosomal recessive mitochondrial disease characterised by congenital cataract, hypertrophic cardiomyopathy, muscle weakness and lactic acidosis after exercise. Biallelic pathogenic mutations in the AGK gene, which encodes the acylglycerol kinase enzyme, cause Sengers syndrome. In addition, heart disease and muscle disease are prevalent, meaning that life expectancy is short for many patients.
