Sarcosinemia (SAR), also called hypersarcosinemia and SARDH deficiency,
is a rare
autosomal
An autosome is any chromosome that is not a sex chromosome. The members of an autosome pair in a diploid cell have the same morphology, unlike those in allosomal (sex chromosome) pairs, which may have different structures. The DNA in autosome ...
recessive
In genetics, dominance is the phenomenon of one variant (allele) of a gene on a chromosome masking or overriding the effect of a different variant of the same gene on the other copy of the chromosome. The first variant is termed dominant and ...
metabolic disorder
A metabolic disorder is a disorder that negatively alters the body's processing and distribution of macronutrients, such as proteins, fats, and carbohydrates. Metabolic disorders can happen when abnormal chemical reactions in the body alter the ...
characterized by an increased concentration of
sarcosine
Sarcosine, also known as ''N''-methylglycine, or monomethylglycine, is a amino acid with the formula CH3N(H)CH2CO2H. It exists at neutral pH as the zwitterion CH3N+(H)2CH2CO2−, which can be obtained as a white, water-soluble powder. Like some ...
in
blood plasma
Blood plasma is a light Amber (color), amber-colored liquid component of blood in which blood cells are absent, but which contains Blood protein, proteins and other constituents of whole blood in Suspension (chemistry), suspension. It makes up ...
and
urine
Urine is a liquid by-product of metabolism in humans and many other animals. In placental mammals, urine flows from the Kidney (vertebrates), kidneys through the ureters to the urinary bladder and exits the urethra through the penile meatus (mal ...
("sarcosinuria"). It can result from an inborn error of
sarcosine
Sarcosine, also known as ''N''-methylglycine, or monomethylglycine, is a amino acid with the formula CH3N(H)CH2CO2H. It exists at neutral pH as the zwitterion CH3N+(H)2CH2CO2−, which can be obtained as a white, water-soluble powder. Like some ...
metabolism, or from severe
folate deficiency
Folate deficiency, also known as vitamin B9 deficiency, is a low level of folate and derivatives in the body. This may result in megaloblastic anemia in which red blood cells become abnormally large, and folate deficiency anemia is the term given ...
related to the
folate
Folate, also known as vitamin B9 and folacin, is one of the B vitamins. Manufactured folic acid, which is converted into folate by the body, is used as a dietary supplement and in food fortification as it is more stable during processing and ...
requirement for the conversion of sarcosine to
glycine
Glycine (symbol Gly or G; ) is an amino acid that has a single hydrogen atom as its side chain. It is the simplest stable amino acid. Glycine is one of the proteinogenic amino acids. It is encoded by all the codons starting with GG (G ...
. It is thought to be a relatively benign condition.
Cause
Sarcosinemia is thought to be caused by a
mutation
In biology, a mutation is an alteration in the nucleic acid sequence of the genome of an organism, virus, or extrachromosomal DNA. Viral genomes contain either DNA or RNA. Mutations result from errors during DNA or viral replication, ...
in the
sarcosine dehydrogenase (SARDH) gene, which is
located at human
chromosome
A chromosome is a package of DNA containing part or all of the genetic material of an organism. In most chromosomes, the very long thin DNA fibers are coated with nucleosome-forming packaging proteins; in eukaryotic cells, the most import ...
9q34.
[
The disease is inherited in an autosomal recessive manner,][ which means the defective gene responsible for the disorder is located on an ]autosome
An autosome is any chromosome that is not a sex chromosome. The members of an autosome pair in a diploid cell have the same morphology, unlike those in allosomal (sex chromosome) pairs, which may have different structures. The DNA in autosomes ...
(chromosome 9 is an autosome), and two copies of the defective gene (one inherited from each parent) are required in order to be born with the disorder. The parents of an individual with an autosomal recessive disorder both carry
Carry or carrying may refer to:
People
*Carry (name)
Finance
* Carried interest (or carry), the share of profits in an investment fund paid to the fund manager
* Carry (investment), a financial term: the carry of an asset is the gain or cost of ...
one copy of the defective gene, but usually do not experience any signs or symptoms of the disorder.
Diagnosis
Treatment
See also
* Inborn errors of metabolism
Inborn errors of metabolism form a large class of genetic diseases involving congenital disorders of enzyme activities. The majority are due to defects of single genes that code for enzymes that facilitate conversion of various substances ( substr ...
References
External links
*
{{Amino acid metabolic pathology
Amino acid metabolism disorders
Autosomal recessive disorders
Rare diseases