GRACILE syndrome | |
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Other names | Growth delay-aminoaciduria-cholestasis-iron overload-lactic acidosis-early death (GRACILE) syndrome, Finnish lethal neonatal metabolic syndrome (FLNMS), lactic acidosis, Finnish, with hepatic hemosiderosis, Fellman syndrome |
This condition is inherited in an autosomal recessive manner. |
GRACILE syndrome is a very rare lethal autosomal recessive genetic disorder, one of the Finnish heritage diseases. GRACILE syndrome has also been found in the UK and Sweden, but not nearly as much as in Finland. [1] It is caused by a mutation in the BCS1L gene and it occurs in approximately 1 out of 50,000 live births in Finnish people. To date, there have only been 32 cases of GRACILE syndrome reported. [2]
GRACILE is an acronym for growth retardation, aminoaciduria (amino acids in the urine), cholestasis, iron overload, lactic acidosis and early death. Prior to birth, the growth of the fetus is abnormally slow. This slow growth leads to a smaller than average newborn that has difficulty growing at a normal rate. [3]
People with GRACILE syndrome can have a wide range of symptoms, but that does not mean every person affected will have the same symptoms as one another[ citation needed ]
It has been determined that 80% - 99% of people with GRACILE syndrome have at least one of these:[ citation needed ]
Other symptoms that happen in a smaller percentage of people with GRACILE syndrome include:
A point mutation in the BCS1L gene found on chromosome 2 has been determined to be the cause of GRACILE syndrome. The BCS1L gene is responsible for the production of the BCS1L protein found in the mitochondria, which is connected to the process of oxidative phosphorylation. In particular, the protein is a key contributor in the formation of Complex III that is part of the electron transport chain. Complex III is still able to be produced, but it is reduced significantly compared to a person without GRACILE syndrome. The deficiency of Complex III is more pronounced in the liver and kidneys, which leads to the symptoms seen in those with GRACILE. [5]
The liver histology shows microvesicular steatosis and cholestasis with abundant iron accumulation in hepatocytes and Kupffer cells. The liver iron content slightly decreases with age, concomitantly with increasing liver fibrosis and cirrhosis. Abnormal transaminases and coagulation are noted.[ citation needed ] There are currently a combination of 55 biochemical and molecular genetics tests that can be completed prior to birth to diagnose GRACILE syndrome. These tests include enzyme assays, deletion/duplication analysis, targeted variant analysis, sequence analysis of select exons, and sequence analysis of the entire coding region. [3]
One Finnish study which followed 25 cases from 18 families found that half the infants died within 3 days of birth and the other half died before 4 months of age. [2] Through cases like this, it has been determined that majority of the newborns with GRACILE syndrome will die within the first few months and the rest will die within a few days. [5]
Wilson's disease is a genetic disorder in which excess copper builds up in the body. Symptoms are typically related to the brain and liver. Liver-related symptoms include vomiting, weakness, fluid build-up in the abdomen, swelling of the legs, yellowish skin, and itchiness. Brain-related symptoms include tremors, muscle stiffness, trouble in speaking, personality changes, anxiety, and psychosis.
Hereditary haemochromatosis type 1 is a genetic disorder characterized by excessive intestinal absorption of dietary iron, resulting in a pathological increase in total body iron stores. Humans, like most animals, have no means to excrete excess iron, with the exception of menstruation which, for the average woman, results in a loss of 3.2 mg of iron.
Leigh syndrome is an inherited neurometabolic disorder that affects the central nervous system. It is named after Archibald Denis Leigh, a British neuropsychiatrist who first described the condition in 1951. Normal levels of thiamine, thiamine monophosphate, and thiamine diphosphate are commonly found, but there is a reduced or absent level of thiamine triphosphate. This is thought to be caused by a blockage in the enzyme thiamine-diphosphate kinase, and therefore treatment in some patients would be to take thiamine triphosphate daily.
Liver disease, or hepatic disease, is any of many diseases of the liver. If long-lasting it is termed chronic liver disease. Although the diseases differ in detail, liver diseases often have features in common.
Aagenaes syndrome is a syndrome characterised by congenital hypoplasia of lymph vessels, which causes lymphedema of the legs and recurrent cholestasis in infancy, and slow progress to hepatic cirrhosis and giant cell hepatitis with fibrosis of the portal tracts.
Alagille syndrome (ALGS) is a genetic disorder that affects primarily the liver and the heart. Problems associated with the disorder generally become evident in infancy or early childhood. The disorder is inherited in an autosomal dominant pattern, and the estimated prevalence of Alagille syndrome is 1 in every 30,000 to 1 in every 40,000 live births. It is named after the French pediatrician Daniel Alagille, who first described the condition in 1969.
Glycogen storage disease type I is an inherited disease that prevents the liver from properly breaking down stored glycogen, which is necessary in 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 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.
Progressive familial intrahepatic cholestasis (PFIC) is a group of familial cholestatic conditions caused by defects in biliary epithelial transporters. The clinical presentation usually occurs first in childhood with progressive cholestasis. This usually leads to failure to thrive, cirrhosis, and the need for liver transplantation.
Oculocerebrorenal syndrome is a rare X-linked recessive disorder characterized by congenital cataracts, hypotonia, intellectual disability, proximal tubular acidosis, aminoaciduria and low-molecular-weight proteinuria. Lowe syndrome can be considered a cause of Fanconi syndrome.
Neonatal cholestasis refers to elevated levels of conjugated bilirubin identified in newborn infants within the first few months of life. Conjugated hyperbilirubinemia is clinically defined as >20% of total serum bilirubin or conjugated bilirubin concentration greater than 1.0 mg/dL regardless of total serum bilirubin concentration. The differential diagnosis for neonatal cholestasis can vary extensively. However, the underlying disease pathology is caused by improper transport and/or defects in excretion of bile from hepatocytes leading to an accumulation of conjugated bilirubin in the body. Generally, symptoms associated with neonatal cholestasis can vary based on the underlying cause of the disease. However, most infants affected will present with jaundice, scleral icterus, failure to thrive, acholic or pale stools, and dark urine.
Pyruvate carboxylase deficiency is an inherited disorder that causes lactic acid to accumulate in the blood. High levels of these substances can damage the body's organs and tissues, particularly in the nervous system. Pyruvate carboxylase deficiency is a rare condition, with an estimated incidence of 1 in 250,000 births worldwide. Type A of the disease appears to be much more common in some Algonkian Indian tribes in eastern Canada, while the type B disease is more present in European populations.
Mitochondrial chaperone BCS1 (BCS1L), also known as BCS1 homolog, ubiquinol-cytochrome c reductase complex chaperone (h-BCS1), is a protein that in humans is encoded by the BCS1L gene. BCS1L is a chaperone protein involved in the assembly of Ubiquinol Cytochrome c Reductase, which is located in the inner mitochondrial membrane and is part of the electron transport chain. Mutations in this gene are associated with mitochondrial complex III deficiency, GRACILE syndrome, and Bjoernstad syndrome.
Juvenile hemochromatosis, also known as hemochromatosis type 2, is a rare form of hereditary hemochromatosis, which emerges in young individuals, typically between 15 and 30 years of age, but occasionally later. It is characterized by an inability to control how much iron is absorbed by the body, in turn leading to iron overload, where excess iron accumulates in many areas of the body and causes damage to the places it accumulates.
Björnstad syndrome is an autosomal recessive congenital condition involving pili torti, sensorineural deafness, and hair abnormalities. It was first characterized in 1965, in Oslo, by prof. Roar Theodor Bjørnstad after he observed an association between pili torti and hearing loss. The condition is extremely rare, with less than 50 cases documented in medical literature worldwide.
Mitochondrially encoded tRNA phenylalanine also known as MT-TF is a transfer RNA which in humans is encoded by the mitochondrial MT-TF gene.
Congenital generalized lipodystrophy is an extremely rare autosomal recessive condition, characterized by an extreme scarcity of fat in the subcutaneous tissues. It is a type of lipodystrophy 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.
Mitochondrial DNA depletion syndrome, or Alper's disease, is any of a group of autosomal recessive disorders that cause a significant drop in mitochondrial DNA in affected tissues. Symptoms can be any combination of myopathic, hepatopathic, or encephalomyopathic. These syndromes affect tissue in the muscle, liver, or both the muscle and brain, respectively. The condition is typically fatal in infancy and early childhood, though some have survived to their teenage years with the myopathic variant and some have survived into adulthood with the SUCLA2 encephalomyopathic variant. There is currently no curative treatment for any form of MDDS, though some preliminary treatments have shown a reduction in symptoms.
COACH syndrome, also known as Joubert syndrome with hepatic defect, is a rare autosomal recessive genetic disease. The name is an acronym of the defining signs: cerebellar vermis aplasia, oligophrenia, congenital ataxia, coloboma and hepatic fibrosis. The condition is associated with moderate intellectual disability. It falls under the category of a Joubart Syndrome-related disorder (JSRD).
Transmembrane protein 70 is a protein that in humans is encoded by the TMEM70 gene. It is a transmembrane protein located in the mitochondrial inner membrane involved in the assembly of the F1 and Fo structural subunits of ATP synthase. Mutations in this gene have been associated with neonatal mitochondrial encephalo-cardiomyopathy due to ATP synthase deficiency, causing a wide variety of symptoms including 3-methylglutaconic aciduria, lactic acidosis, mitochondrial myopathy, and cardiomyopathy.