237 articles
Glutathione synthetase deficiency
Glutathione synthetase deficiency, also called 5-oxoprolinuria or pyroglutamic aciduria, is a rare autosomal recessive GSS-gene metabolic disorder causing low glutathione, hemolytic anemia, metabolic acidosis, and neurological damage, treated with bicarbonate and vitamins C and E.
Glycine encephalopathy
Glycine encephalopathy, or nonketotic hyperglycinemia (NKH), is an autosomal recessive inborn error of glycine metabolism caused by glycine cleavage system defects (GLDC, AMT), causing neonatal lethargy, hypotonia, apnea, and seizures; treated with sodium benzoate and supportive care.
Glycogen storage disease due to aldolase A deficiency
Glycogen storage disease due to aldolase A deficiency (GSD type XII, GSD12, OMIM 611881) is an ultra-rare autosomal recessive ALDOA disorder causing hemolytic anemia, fever-triggered rhabdomyolysis, and learning disabilities, with no specific treatment.
Glycogen storage disease due to glucose-6-phosphatase deficiency
Glycogen storage disease due to glucose-6-phosphatase deficiency (GSD I, von Gierke disease): autosomal recessive disorder of G6PC or SLC37A4 causing fasting hypoglycemia, hepatomegaly, treated with cornstarch and glucose regimens.
Glycogen storage disease due to glycogen branching enzyme deficiency
Glycogen storage disease type IV, Andersen disease, amylopectinosis: autosomal recessive GBE1 (3p12) deficiency causing polyglucosan accumulation; hepatic, neuromuscular, cardiac continuum from fetal onset to adult polyglucosan body disease.
Glycogen storage disease due to hepatic glycogen synthase deficiency
Glycogen storage disease type 0a (GSD 0a, hepatic glycogen synthase deficiency, GYS2, OMIM 240600): rare autosomal recessive liver glycogen synthesis defect causing fasting ketotic hypoglycemia without hepatomegaly and postprandial hyperglycemia.
Glycogen storage disease due to liver and muscle phosphorylase kinase deficiency
Glycogen storage disease due to liver and muscle phosphorylase kinase deficiency, also called GSD IXb or PHKB-related GSD IX, is an autosomal recessive glycogenolysis defect causing hepatomegaly, hypoglycemia, and mild muscle involvement, managed with diet and uncooked cornstarch.
Glycogen storage disease due to liver glycogen phosphorylase deficiency
Glycogen storage disease type VI, also called Hers disease, is a rare autosomal recessive liver glycogenosis caused by PYGL deficiency of hepatic glycogen phosphorylase, causing hepatomegaly, growth delay, and ketotic hypoglycemia.
Glycogen storage disease due to liver phosphorylase kinase deficiency
Liver phosphorylase kinase deficiency (GSD IXa/IXb/IXc; formerly GSD VIa, VIII) is an inherited glycogen storage disease causing hepatomegaly, fasting hypoglycemia, and elevated transaminases; genes PHKA2, PHKB, PHKG2.
Glycogen storage disease due to muscle beta-enolase deficiency
Glycogen storage disease type XIII (GSDXIII, GSD13, muscle enolase deficiency) is an extremely rare autosomal-recessive ENO3 metabolic myopathy causing exercise intolerance, myalgia, and rhabdomyolysis from muscle beta-enolase deficiency.
Glycogen storage disease due to muscle glycogen phosphorylase deficiency
Glycogen storage disease type V, McArdle disease, myophosphorylase deficiency: autosomal recessive PYGM (11q13) disorder blocking muscle glycogen breakdown, causing exercise intolerance, second wind, rhabdomyolysis, and myoglobinuria; managed with carbohydrate-rich diet and supervised aerobic exercise.
Glycogen storage disease due to muscle phosphofructokinase deficiency
Tarui disease (垂井病), glycogen storage disease type VII, muscle phosphofructokinase deficiency: autosomal recessive PFKM defect blocking glycolysis, causing exercise intolerance, cramps, hemolysis, hyperuricemia; described 1965.
Glycogen storage disease due to phosphoglycerate mutase deficiency
Glycogen storage disease type X, also called GSD10 or muscle phosphoglycerate mutase deficiency, is a rare autosomal recessive myopathy causing exercise intolerance, cramps, and rhabdomyolysis, first described in 1981.
Glycogen storage diseases
Glycogen storage disease (GSD), also called glycogenosis, is an inherited metabolic disorder in which defective enzymes prevent normal glycogen breakdown, affecting mainly the liver and muscles.
GM2 gangliosidosis, AB variant
GM2 gangliosidosis, AB variant (GM2 activator deficiency, OMIM 272750) is an ultra-rare autosomal recessive lysosomal storage disorder: GM2A mutations disable the GM2 activator protein, so GM2 ganglioside accumulates despite normal hexosaminidase A and B, causing infantile Tay-Sachs-like neurodegeneration.
GRACILE syndrome
GRACILE syndrome (Fellman disease), a lethal Finnish neonatal mitochondrial disorder from BCS1L mutations, causes growth restriction, aminoaciduria, cholestasis, iron overload, lactic acidosis, and death within months.
Growth delay due to insulin-like growth factor type 1 deficiency
Growth delay due to IGF-1 deficiency (ORPHA:73272, OMIM 608747), also called growth delay-deafness-intellectual disability syndrome: an autosomal recessive IGF1-gene disorder with intrauterine and postnatal growth retardation, sensorineural deafness, and intellectual deficit; under 1 per million, about four reported cases.
Guanidinoacetate methyltransferase deficiency
Guanidinoacetate methyltransferase (GAMT) deficiency is an inherited metabolic disorder in which the body cannot make creatine and guanidinoacetate accumulates, causing epilepsy, intellectual disability, and treatable neurological disease.
Haptocorrin deficiency
Haptocorrin deficiency (transcobalamin I deficiency, TCI deficiency, OMIM 193090) is a rare benign autosomal recessive cobalamin transport disorder causing low serum B12 with normal MMA, homocysteine, and no symptoms.
Harderoporphyria
Harderoporphyria (HARPO), a rare autosomal recessive erythropoietic variant of hereditary coproporphyria caused by biallelic CPOX mutations such as K404E, presents neonatally with hemolytic anemia, jaundice, and massive fecal harderoporphyrin excretion.
Hartnup disease
Hartnup disease (Hartnup disorder), an autosomal recessive SLC6A19/B0AT1 transport defect causing neutral aminoaciduria, pellagra-like photosensitive rash, ataxia, and psychiatric symptoms, treated with nicotinamide and a high-protein diet.
Hawkinsinuria
Hawkinsinuria (4-HPPD deficiency, OMIM 140350) is a rare autosomal dominant tyrosine metabolism disorder caused by HPD gene variants, causing infantile failure to thrive, metabolic acidosis, sparse hair, and lifelong urinary hawkinsin excretion.
Hereditary butyrylcholinesterase deficiency
Hereditary butyrylcholinesterase deficiency (pseudocholinesterase deficiency), an autosomal recessive BCHE disorder on chromosome 3q26, causes prolonged apnea after succinylcholine or mivacurium; managed with ventilation, no specific treatment.
Hereditary coproporphyria
Hereditary coproporphyria (HCP) is a rare autosomal dominant acute hepatic porphyria caused by CPOX enzyme deficiency, causing neurovisceral attacks, rare skin lesions, low penetrance, and treatment with hemin.
Hereditary hypophosphatemic rickets with hypercalciuria
Hereditary hypophosphatemic rickets with hypercalciuria (HHRH, OMIM 241530) is a rare autosomal recessive SLC34A3/NPT2c disorder causing renal phosphate wasting, hypophosphatemia, elevated calcitriol, hypercalciuria, rickets, and kidney stones; treated with phosphate alone.
Hereditary xanthinuria
Hereditary xanthinuria (classic xanthinuria, xanthine stone disease, ORPHA:3467) is a rare autosomal recessive purine metabolism disorder caused by XDH or MOCOS mutations, causing hypouricemia, high urinary xanthine, and xanthine kidney stones in about half of patients.
Histidinemia
Histidinemia (histidase deficiency, HAL deficiency) is a benign autosomal recessive metabolic disorder with elevated histidine in blood, urine, and CSF, caused by HAL gene mutations at 12q22-q24.1.
Homocystinuria
Homocystinuria (HCU), also called classic homocystinuria when caused by CBS deficiency, is a rare autosomal recessive metabolic disorder of homocysteine breakdown, causing lens dislocation, skeletal changes, and thromboembolism, treated with vitamin B6, low-methionine diet, and betaine.
Homocystinuria without methylmalonic aciduria
Homocystinuria without methylmalonic aciduria (functional methionine synthase deficiency; cblE, cblG, cblDv1) is a rare autosomal recessive cobalamin metabolism disorder with megaloblastic anemia, high homocysteine, low methionine, and normal methylmalonic acid, treated with hydroxocobalamin.
HSD10 disease
HSD10 disease, also called HSD10 mitochondrial disease, is a rare X-linked neurometabolic disorder caused by HSD17B10 gene variants, fatal in most affected boys by early childhood.