What causes Refsum disease?
What causes Refsum disease?
Refsum disease is caused by a change (mutation) in the gene that makes an enzyme responsible for breaking down phytanic acid, a particular type of fatty acid which is derived by bacterial fermentation of green plants or algae.
What causes infantile Refsum disease?
What Causes Infantile Refsum Disease? IRD is caused by abnormal changes (mutations) in one of several different genes called PEX genes. These genes are responsible for the function of cell structures called peroxisomes. Mutations in any of the PEX genes can cause problems with the growth and function of peroxisomes.
What does Refsum disease affect?
Adult Refsum disease (ARD) is a rare genetic disease that causes weakness or numbness of the hands and feet (peripheral neuropathy). Due to a genetic abnormality, people with ARD disease lack the enzyme in peroxisomes that break down phytanic acid, a type of fat found in certain foods.
What is peroxisomal disorder?
Peroxisomal disorders are a heterogeneous group of inborn errors of metabolism that result in impairment of peroxisome function. In most cases, this results in neurologic dysfunction of varying extent. The major peroxisomal disorders will be reviewed here.
Who discovered Refsum disease?
Refsum disease was first recognized as a distinct disease entity by Sigvald Refsum in the 1940s. The discovery of markedly elevated levels of the branched-chain fatty acid phytanic acid in certain patients marked Refsum disease as a disorder of lipid metabolism.
What diseases are caused by peroxisome?
Peroxisomal Disorders
- X-linked adrenoleukodystrophy.
- Zellweger syndrome (ZS), neonatal adrenoleukodystrophy, and infantile Refsum disease (IRD)
- Refsum disease.
- Rhizomelic chondrodysplasia punctata.
- More Information.
What happens if peroxisomes are defective?
Peroxisomes produce cholesterol and phospholipids found in brain and heart tissue. A peroxisome protein is involved in preventing one cause of kidney stones. In plants a type of peroxisome converts fatty acids to carbohydrates. Several rare inherited malfunctions of peroxisomes can lead to death.
What is peroxisome biogenesis disorder?
The peroxisome biogenesis disorders (PBD) are a heterogeneous group of autosomal recessive disorders in which peroxisome assembly is impaired, leading to multiple peroxisome enzyme deficiencies, complex developmental sequelae and progressive disabilities.
What is Zellweger’s disease?
What is Zellweger syndrome? Zellweger syndrome (ZS) is a genetic disorder found in newborn babies. ZS is the most severe of the four disorders in the Zellweger spectrum. It causes serious problems with nerves and metabolism (changing food into energy) soon after birth. ZS affects the brain, liver and kidneys.
Which carbon is involved in omega oxidation?
Omega oxidation (ω-oxidation) is a process of fatty acid metabolism in some species of animals. It is an alternative pathway to beta oxidation that, instead of involving the β carbon, involves the oxidation of the ω carbon (the carbon most distant from the carboxyl group of the fatty acid).
What happens if peroxisome is defective?
Defects or a loss of ALD protein lead to an accumulation of VLCFA, and clinically to progressive demyelination/neurodegeneration in the central nervous system, adrenal insufficiency and death within a few years (21).
Which enzymes are deficient in Refsum’s disease?
The single enzyme deficient in classical Refsum’s disease is phytanoyl‐CoA hydroxylase.
What is Refsum disease?
Refsum disease is sometimes called adult Refsum disease or classic Refsum disease. It was first described by Dr. Sigwald Refsum in 1946.
Does Refsum’s disease affect lipid metabolism?
Two siblings with Refsum’s disease, an inherited disorder of lipid metabolism, oxidized intravenously injected uniformly labeled phytanic acid-C (14) at rates less than 5 percent of those found in normal subjects. The defect in oxidation of phytanic acid persisted in cultures of fibroblasts from the patients’ skin.
What is the pathophysiology of Refsum disease and Zellweger syndrome?
A peripheral neuropathy has rarely been reported in the infantile Refsum disease and the Zellweger syndrome. Adult Refsum disease (ARD, OMIM #266500) is an autosomal peroxisomal disease caused by the accumulation of phytanic acid in tissues.
