Browsing Pathways

Gamma-cystathionase deficiency, also called cystathionase deficiency, is an autosomal recessive metabolic disorder caused by a defective cystathionine gamma-lyase. Cystathionine gamma-lyase catalyzes the conversion of L-Serine and homocysteine into L-Cystathionine which is the substrate of cystathionine gamma-lyase. This disorder is characterized by a large accumulation of L-Cystathionine in the cell. Symptoms of the disorder include mental deficiency and seizure. Since there is currently no cure forGamma-cystathionase deficiency, treatment involves managing the disorder's symptoms.

Gamma-cystathionase deficiency, also called cystathionase deficiency, is an autosomal recessive metabolic disorder caused by a defective cystathionine gamma-lyase. Cystathionine gamma-lyase catalyzes the conversion of L-Serine and homocysteine into L-Cystathionine which is the substrate of cystathionine gamma-lyase. This disorder is characterized by a large accumulation of L-Cystathionine in the cell. Symptoms of the disorder include mental deficiency and seizure. Since there is currently no cure forGamma-cystathionase deficiency, treatment involves managing the disorder's symptoms.

Gamma-Glutamyltransferase Deficiency is an autosomal recessive disorder caused by a mutation in the GGT1 gene which codes for gamma-glutamyltranspeptidase 1. A deficiency in this enzyme results in accumulation of L-cysteine, gamma-glutamylcysteine, and glutathione in urine. Symptoms, which present at birth, include tall stature, psychosis, and mental retardation.

Gamma-Glutamyltransferase Deficiency is an autosomal recessive disorder caused by a mutation in the GGT1 gene which codes for gamma-glutamyltranspeptidase 1. A deficiency in this enzyme results in accumulation of L-cysteine, gamma-glutamylcysteine, and glutathione in urine. Symptoms, which present at birth, include tall stature, psychosis, and mental retardation.

Gamma-glutamyltranspeptidase deficiency, characterized by glutathionemia and glutathionuria, is an autosomal recessive disorder of glutathione metabolism caused by a defective gamma-glutamyl transpeptidase (GGT). GGT transfers glutamyl moieties to acceptor molecules such as amino acids and peptides. This disorder is characterized by a large accumulation of glutathione in the urine. Symptoms of the disorder include easy bruising, asthma, and mild mental retardation.

Gamma-glutamyltranspeptidase deficiency, characterized by glutathionemia and glutathionuria, is an autosomal recessive disorder of glutathione metabolism caused by a defective gamma-glutamyl transpeptidase (GGT). GGT transfers glutamyl moieties to acceptor molecules such as amino acids and peptides. This disorder is characterized by a large accumulation of glutathione in the urine. Symptoms of the disorder include easy bruising, asthma, and mild mental retardation.

Gaucher disease, also known as glucocerebrosidase deficiency, acid beta-glucosidase deficiency or GBA deficiency, refers to a group of autosomal recessively inherited rare inborn error of metabolism (IEM) that affect the sphingolipid metabolism pathway. All forms of Gaucher disease is caused by a mutation in the GBA gene that encodes lysosomal acid glucosylceramidase, an enzyme that is responsible for catalyzing the formation of ceramide and glucose from glucosylceramide via a hydrolysis reaction. Gaucher disease is characterized by the intracellular buildup of glucosylceramides, particularly in phagocytes, forming what are known as Gaucher cells. Symptoms include anemia, fatigue, hepatomegaly and splenomegaly, however these may vary based on the type of Gaucher disease. For example, type 1 (GD1) involves hepato- and splenomegaly, and types 2 and 3 (GD2 and GD3) also typically affect the brain and spinal cord, and as such tend to be more severe and more likely to become lethal. Treatment for Gaucher disease includes enzyme replacement therapy for type 1, which also helps treat types 2 and 3, but as the enzymes cannot cross the blood-brain barrier, cannot help with the brain damage associated with these types. A drug called miglustat, sold as Zavesca, can also be used to treat the symptoms of type 1 Gaucher disease in individuals who cannot have enzyme replacement therapy. It is estimated that Gaucher disease affects 1 in 100,000 individuals, with the rates being higher in certain populations such as Ashkenazi Jews. GD1 is the most common in most populations representing around 90% of cases of Gaucher disease, with GD2 and GD3 representing roughly 5% each.

Gaucher disease, also known as glucocerebrosidase deficiency, acid beta-glucosidase deficiency or GBA deficiency, refers to a group of autosomal recessively inherited rare inborn error of metabolism (IEM) that affect the sphingolipid metabolism pathway. All forms of Gaucher disease is caused by a mutation in the GBA gene that encodes lysosomal acid glucosylceramidase, an enzyme that is responsible for catalyzing the formation of ceramide and glucose from glucosylceramide via a hydrolysis reaction. Gaucher disease is characterized by the intracellular buildup of glucosylceramides, particularly in phagocytes, forming what are known as Gaucher cells. Symptoms include anemia, fatigue, hepatomegaly and splenomegaly, however these may vary based on the type of Gaucher disease. For example, type 1 (GD1) involves hepato- and splenomegaly, and types 2 and 3 (GD2 and GD3) also typically affect the brain and spinal cord, and as such tend to be more severe and more likely to become lethal. Treatment for Gaucher disease includes enzyme replacement therapy for type 1, which also helps treat types 2 and 3, but as the enzymes cannot cross the blood-brain barrier, cannot help with the brain damage associated with these types. A drug called miglustat, sold as Zavesca, can also be used to treat the symptoms of type 1 Gaucher disease in individuals who cannot have enzyme replacement therapy. It is estimated that Gaucher disease affects 1 in 100,000 individuals, with the rates being higher in certain populations such as Ashkenazi Jews. GD1 is the most common in most populations representing around 90% of cases of Gaucher disease, with GD2 and GD3 representing roughly 5% each.

Globoid Cell Leukodistrophy (GLD), also called Krabbe disease and galactosylceramide lipidosis, is an extremely rare inherited inborn error of metabolism (IEM). It is a degenerative disorder that affects the nervous system. It has an estimated prevalence of 1/100,000 in the Northern European population and a worldwide incidence of 1/100,000-1/250,000 live births. GLD is an autosomal recessive disorder that is caused by a deficiency of an enzyme called galactosylceramidase. Galactosylceramidase is a lysosomal protein that hydrolyzes the galactose ester bonds of ceramides and ceramide derivatives including galactocerebroside, galactosylsphingosine (psychosine), lactosylceramide, and monogalactosyldiglyceride. More specifically, galactosylceramidase is an enzyme that is involved in the catabolism (via the removal of galactose) of galactosylceramide, a major lipid in myelin, kidney, and epithelial cells of the small intestine and colon. Defects in galactosylceramidase lead to the accumulation of cytotoxic psychosine, which ultimately leads to apoptosis of oligodendrocytes and demyelination. As a result, this enzyme deficiency impairs the growth and maintenance of myelin, the protective sheath around nerve cell axons that ensures that electrical impulses are rapidly transmitted. GLD is part of a group of disorders known as leukodystrophies, which result from the loss of myelin (demyelination). GLD is also characterized by the abnormal presence of globoid cells, which are globe-shaped cells that often have multiple nuclei. There are three different phenotypes for GLD: infantile, juvenile, and late-onset. Neurodegeneration and early death (at age 2-3) occur in most infantile cases. In juvenile patients, the disease is often fatal 2-7 years after the symptoms begin. Adult-onset patients can survive many years after symptoms first manifest. The symptoms of infantile GLD usually begin during the first year of life. Typically, the initial signs and symptoms include feeding difficulties, episodes of fever without any sign of infection, irritability, stiff posture, muscle weakness, and slowed mental and physical development. Muscles continue to weaken as the disease progresses which decreases the infant's ability to move, chew, swallow, and breathe. It is also common for affected infants to experience vision loss and seizures. Treatment is limited to hematopoietic stem cell transplantation in pre-symptomatic infantile patients and mildly affected late-onset patients. Stem cell transplants have been shown to slow the progression of the disease.

Globoid Cell Leukodistrophy (GLD), also called Krabbe disease and galactosylceramide lipidosis, is an extremely rare inherited inborn error of metabolism (IEM). It is a degenerative disorder that affects the nervous system. It has an estimated prevalence of 1/100,000 in the Northern European population and a worldwide incidence of 1/100,000-1/250,000 live births. GLD is an autosomal recessive disorder that is caused by a deficiency of an enzyme called galactosylceramidase. Galactosylceramidase is a lysosomal protein that hydrolyzes the galactose ester bonds of ceramides and ceramide derivatives including galactocerebroside, galactosylsphingosine (psychosine), lactosylceramide, and monogalactosyldiglyceride. More specifically, galactosylceramidase is an enzyme that is involved in the catabolism (via the removal of galactose) of galactosylceramide, a major lipid in myelin, kidney, and epithelial cells of the small intestine and colon. Defects in galactosylceramidase lead to the accumulation of cytotoxic psychosine, which ultimately leads to apoptosis of oligodendrocytes and demyelination. As a result, this enzyme deficiency impairs the growth and maintenance of myelin, the protective sheath around nerve cell axons that ensures that electrical impulses are rapidly transmitted. GLD is part of a group of disorders known as leukodystrophies, which result from the loss of myelin (demyelination). GLD is also characterized by the abnormal presence of globoid cells, which are globe-shaped cells that often have multiple nuclei. There are three different phenotypes for GLD: infantile, juvenile, and late-onset. Neurodegeneration and early death (at age 2-3) occur in most infantile cases. In juvenile patients, the disease is often fatal 2-7 years after the symptoms begin. Adult-onset patients can survive many years after symptoms first manifest. The symptoms of infantile GLD usually begin during the first year of life. Typically, the initial signs and symptoms include feeding difficulties, episodes of fever without any sign of infection, irritability, stiff posture, muscle weakness, and slowed mental and physical development. Muscles continue to weaken as the disease progresses which decreases the infant's ability to move, chew, swallow, and breathe. It is also common for affected infants to experience vision loss and seizures. Treatment is limited to hematopoietic stem cell transplantation in pre-symptomatic infantile patients and mildly affected late-onset patients. Stem cell transplants have been shown to slow the progression of the disease.