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Combined Malonic And Methylmalonic Aciduria
Combined malonic and methylmalonic aciduria (CMAMMA), also called combined malonic and methylmalonic acidemia is an inherited metabolic disease characterized by elevated levels of malonic acid and methylmalonic acid. Some researchers have hypothesized that CMAMMA might be one of the most common forms of methylmalonic acidemia, and possibly one of the most common inborn errors of metabolism. Due to being infrequently diagnosed, it most often goes undetected. Symptoms and signs The clinical phenotypes of CMAMMA are highly heterogeneous and range from asymptomatic, mild to severe symptoms. The underlying pathophysiology is not yet understood. The following symptoms are reported in the literature: * metabolic acidosis * coma * hypoglycemia * seizures * gastrointestinal disease * developmental delay * speech delay * failure to thrive * psychiatric disease * memory problems * cognitive decline * encephalopathy * cardiomyopathy * dysmorphic features When the first symptoms appear in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metabolic Disease
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 normal metabolic process. It can also be defined as inherited single gene anomaly, most of which are autosomal recessive. Signs and symptoms Some of the symptoms that can occur with metabolic disorders are lethargy, weight loss, jaundice and seizures. The symptoms expressed would vary with the type of metabolic disorder. There are four categories of symptoms: acute symptoms, late-onset acute symptoms, progressive general symptoms and permanent symptoms. Causes Inherited metabolic disorders are one cause of metabolic disorders, and occur when a defective gene causes an enzyme deficiency. These diseases, of which there are many subtypes, are known as inborn errors of metabolism. Metabolic diseases can also occur when the liver or pancrea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mitochondrial
A mitochondrion (; ) is an organelle found in the cells of most Eukaryotes, such as animals, plants and fungi. Mitochondria have a double membrane structure and use aerobic respiration to generate adenosine triphosphate (ATP), which is used throughout the cell as a source of chemical energy. They were discovered by Albert von Kölliker in 1857 in the voluntary muscles of insects. The term ''mitochondrion'' was coined by Carl Benda in 1898. The mitochondrion is popularly nicknamed the "powerhouse of the cell", a phrase coined by Philip Siekevitz in a 1957 article of the same name. Some cells in some multicellular organisms lack mitochondria (for example, mature mammalian red blood cells). A large number of unicellular organisms, such as microsporidia, parabasalids and diplomonads, have reduced or transformed their mitochondria into other structures. One eukaryote, ''Monocercomonoides'', is known to have completely lost its mitochondria, and one multicellular organism, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methylmalonyl-CoA
Methylmalonyl-CoA is the thioester consisting of coenzyme A linked to methylmalonic acid. It is an important intermediate in the biosynthesis of succinyl-CoA, which plays an essential role in the tricarboxylic acid cycle (aka the Citric Acid Cycle, or Krebs Cycle). The compound is sometimes referred to as "methylmalyl-CoA". Biosynthesis and metabolism Methylmalonyl-CoA results from the metabolism of fatty acid with an odd number of carbons or from cholesterol side-chains, forming Propionyl-CoA. Propionyl-CoA and bicarbonate are converted to Methylmalonyl-CoA by the enzyme propionyl-CoA Carboxylase. It then is converted into succinyl-CoA by methylmalonyl-CoA mutase (MUT). This reaction is a reversible isomerization. In this way, the compound enters the Citric Acid Cycle. The following diagram demonstrates the aforementioned reaction: Propionyl CoA + Bicarbonate → Methylmalonyl CoA → Succinyl CoA Vitamin B12 Vitamin B12 plays an integral role in this reaction. Coenzyme ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Malonyl-CoA
Malonyl-CoA is a coenzyme A derivative of malonic acid. Functions It plays a key role in chain elongation in fatty acid biosynthesis and polyketide biosynthesis. Fatty acid biosynthesis Malonyl-CoA provides 2-carbon units to fatty acids and commits them to fatty acid chain synthesis. Malonyl-CoA is formed by carboxylating acetyl-CoA using the enzyme acetyl-CoA carboxylase. One molecule of acetyl-CoA joins with a molecule of bicarbonate,Nelson D, Cox M (2008) ''Lehninger principles of biochemistry''. 5th Ed: p. 806 requiring energy rendered from ATP. Malonyl-CoA is utilised in fatty acid biosynthesis by the enzyme malonyl coenzyme A:acyl carrier protein transacylase (MCAT). MCAT serves to transfer malonate from malonyl-CoA to the terminal thiol of ''holo''-acyl carrier protein (ACP). Polyketide biosynthesis MCAT is also involved in bacterial polyketide biosynthesis. The enzyme MCAT together with an acyl carrier protein (ACP), and a polyketide synthase (PKS) and chain-length f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Minor Allele Frequency
Minor allele frequency (MAF) is the frequency at which the ''second most common'' allele occurs in a given population. They play a surprising role in heritability since MAF variants which occur only once, known as "singletons", drive an enormous amount of selection. Single nucleotide polymorphisms (SNPs) with a minor allele frequency of 0.05 (5%) or greater were targeted by the HapMap project. MAF is widely used in population genetics studies because it provides information to differentiate between common and rare variants in the population. As an example, a 2015 study sequenced the whole genomes of Sardinian individuals. The authors classified the variants found in the study in three classes according to their MAF. It was observed that rare variants (MAF 0.05) in this population. Interpreting MAF data 1. Introduce the reference of a SNP of interest, as an example: rs429358, in a database (dbSNP or other). 2. Find MAF/MinorAlleleCount link. MAF/MinorAlleleCount: C=0.1506/ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Compound Heterozygous
In medical genetics, compound heterozygosity is the condition of having two or more heterogeneous recessive alleles at a particular locus that can cause genetic disease in a heterozygous state; that is, an organism is a compound heterozygote when it has two recessive alleles for the same gene, but with those two alleles being different from each other (for example, both alleles might be mutated but at different locations). Compound heterozygosity reflects the diversity of the mutation base for many autosomal recessive genetic disorders; mutations in most disease-causing genes have arisen many times. This means that many cases of disease arise in individuals who have two unrelated alleles, who technically are heterozygotes, but both the alleles are defective. These disorders are often best known in some classic form, such as the homozygous recessive case of a particular mutation that is widespread in some population. In its compound heterozygous forms, the disease may have lower penet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Homozygous
Zygosity (the noun, zygote, is from the Greek "yoked," from "yoke") () is the degree to which both copies of a chromosome or gene have the same genetic sequence. In other words, it is the degree of similarity of the alleles in an organism. Most eukaryotes have two matching sets of chromosomes; that is, they are diploid. Diploid organisms have the same loci on each of their two sets of homologous chromosomes except that the sequences at these loci may differ between the two chromosomes in a matching pair and that a few chromosomes may be mismatched as part of a chromosomal sex-determination system. If both alleles of a diploid organism are the same, the organism is homozygous at that locus. If they are different, the organism is heterozygous at that locus. If one allele is missing, it is hemizygous, and, if both alleles are missing, it is nullizygous. The DNA sequence of a gene often varies from one individual to another. These gene variants are called alleles. While some gen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Exon
An exon is any part of a gene that will form a part of the final mature RNA produced by that gene after introns have been removed by RNA splicing. The term ''exon'' refers to both the DNA sequence within a gene and to the corresponding sequence in RNA transcripts. In RNA splicing, introns are removed and exons are covalently joined to one another as part of generating the mature RNA. Just as the entire set of genes for a species constitutes the genome, the entire set of exons constitutes the exome. History The term ''exon'' derives from the expressed region and was coined by American biochemist Walter Gilbert in 1978: "The notion of the cistron… must be replaced by that of a transcription unit containing regions which will be lost from the mature messengerwhich I suggest we call introns (for intragenic regions)alternating with regions which will be expressedexons." This definition was originally made for protein-coding transcripts that are spliced before being translated. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Locus (genetics)
In genetics, a locus (plural loci) is a specific, fixed position on a chromosome where a particular gene or genetic marker is located. Each chromosome carries many genes, with each gene occupying a different position or locus; in humans, the total number of protein-coding genes in a complete haploid set of 23 chromosomes is estimated at 19,000–20,000. Genes may possess multiple variants known as alleles, and an allele may also be said to reside at a particular locus. Diploid and polyploid cells whose chromosomes have the same allele at a given locus are called homozygous with respect to that locus, while those that have different alleles at a given locus are called heterozygous. The ordered list of loci known for a particular genome is called a gene map. Gene mapping is the process of determining the specific locus or loci responsible for producing a particular phenotype or biological trait. Association mapping, also known as "linkage disequilibrium mapping", is a method of ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chromosome 16
Chromosome 16 is one of the 23 pairs of chromosomes in humans. People normally have two copies of this chromosome. Chromosome 16 spans about 90 million base pair A base pair (bp) is a fundamental unit of double-stranded nucleic acids consisting of two nucleobases bound to each other by hydrogen bonds. They form the building blocks of the DNA double helix and contribute to the folded structure of both DNA ...s (the building material of DNA) and represents just under 3% of the total DNA in cell (biology), cells. Genes Number of genes The following are some of the gene count estimates of human chromosome 16. Because researchers use different approaches to genome annotation their predictions of the number of genes on each chromosome varies (for technical details, see gene prediction). Among various projects, the collaborative consensus coding sequence project (Consensus CDS Project, CCDS) takes an extremely conservative strategy. So CCDS's gene number prediction represents a lowe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Autosomal 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 the second recessive. This state of having two different variants of the same gene on each chromosome is originally caused by a mutation in one of the genes, either new (''de novo'') or inherited. The terms autosomal dominant or autosomal recessive are used to describe gene variants on non-sex chromosomes ( autosomes) and their associated traits, while those on sex chromosomes (allosomes) are termed X-linked dominant, X-linked recessive or Y-linked; these have an inheritance and presentation pattern that depends on the sex of both the parent and the child (see Sex linkage). Since there is only one copy of the Y chromosome, Y-linked traits cannot be dominant or recessive. Additionally, there are other forms of dominance such as incomplete d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MLYCD
Malonyl-CoA decarboxylase (), (which can also be called MCD and malonyl-CoA carboxyl-lyase) is found in bacteria and humans and has important roles in regulating fatty acid metabolism and food intake, and it is an attractive target for drug discovery. It is an enzyme associated with Malonyl-CoA decarboxylase deficiency. In humans, it is encoded by the MLYCD gene. Its main function is to catalyze the conversion of malonyl-CoA into acetyl-CoA and carbon dioxide. It is involved in fatty acid biosynthesis. To some degree, it reverses the action of Acetyl-CoA carboxylase. Structure MCD presents two isoforms which can be transcribed form one gene: a long isoform (54kDa), distributed in mitochondria, and a short isoform (49kDa) that can be found in peroxisomes and cytosol. The long isoform includes a sequence of signaling towards mitochondria in the N-terminus; whereas the short one only contains the typical sequence of peroxisomal signaling PTS1 in the C-terminus, also shared by t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
