Biomaterial Database

Quantitative variations of red-cell cytochrome b5 reductase (NADH-methemoglobin-reductase) in the Algerian population: evidence for defective alleles. 1981

A Reghis, and M Benabadji, and P Tchen, and J C Kaplan

A striking proportion of Algerian subjects was reported among patients with congenital recessive methemoglobinemia due to cytochrome b5 reductase deficiency (Kaplan et al. 1979). A population survey was carried out in red blood cells from 1000 Algerian subjects. In 16 subjects, the cytochrome b2 reductase activity was diminished by 50%. Family studies indicated the presence of a defective allele with an overall gene frequency of 0.008. Immunologically cross-reacting material was found in red cells with low cytochrome b5 reductase activity. Leukocytes exhibited normal levels of enzyme in some families and low levels in others suggesting that at least two different deficient alleles at the DIA1 locus were present in the Algerian population. A higher prevalence of the deficient allele(s) was found in subjects of Kabyle origin.

UI	MeSH Term	Description	Entries
D008708	Methemoglobinemia	The presence of methemoglobin in the blood, resulting in cyanosis. A small amount of methemoglobin is present in the blood normally, but injury or toxic agents convert a larger proportion of hemoglobin into methemoglobin, which does not function reversibly as an oxygen carrier. Methemoglobinemia may be due to a defect in the enzyme NADH methemoglobin reductase (an autosomal recessive trait) or to an abnormality in hemoglobin M (an autosomal dominant trait). (Dorland, 27th ed)	Methemoglobinemias
D009247	NADH, NADPH Oxidoreductases	A group of oxidoreductases that act on NADH or NADPH. In general, enzymes using NADH or NADPH to reduce a substrate are classified according to the reverse reaction, in which NAD+ or NADP+ is formally regarded as an acceptor. This subclass includes only those enzymes in which some other redox carrier is the acceptor. (Enzyme Nomenclature, 1992, p100) EC 1.6.	Oxidoreductases, NADH, NADPH,NADPH Oxidoreductases NADH,Oxidoreductases NADH, NADPH
D010375	Pedigree	The record of descent or ancestry, particularly of a particular condition or trait, indicating individual family members, their relationships, and their status with respect to the trait or condition.	Family Tree,Genealogical Tree,Genealogic Tree,Genetic Identity,Identity, Genetic,Family Trees,Genealogic Trees,Genealogical Trees,Genetic Identities,Identities, Genetic,Tree, Family,Tree, Genealogic,Tree, Genealogical,Trees, Family,Trees, Genealogic,Trees, Genealogical
D005787	Gene Frequency	The proportion of one particular in the total of all ALLELES for one genetic locus in a breeding POPULATION.	Allele Frequency,Genetic Equilibrium,Equilibrium, Genetic,Allele Frequencies,Frequencies, Allele,Frequencies, Gene,Frequency, Allele,Frequency, Gene,Gene Frequencies
D005808	Genes, Recessive	Genes that influence the PHENOTYPE only in the homozygous state.	Conditions, Recessive Genetic,Genetic Conditions, Recessive,Recessive Genetic Conditions,Condition, Recessive Genetic,Gene, Recessive,Genetic Condition, Recessive,Recessive Gene,Recessive Genes,Recessive Genetic Condition
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000462	Algeria	A country in northern Africa bordering the Mediterranean Sea, between MOROCCO and TUNISIA. Its capital is Algiers.
D014644	Genetic Variation	Genotypic differences observed among individuals in a population.	Genetic Diversity,Variation, Genetic,Diversity, Genetic,Diversities, Genetic,Genetic Diversities,Genetic Variations,Variations, Genetic
D042966	Cytochrome-B(5) Reductase	A FLAVOPROTEIN oxidoreductase that occurs both as a soluble enzyme and a membrane-bound enzyme due to ALTERNATIVE SPLICING of a single mRNA. The soluble form is present mainly in ERYTHROCYTES and is involved in the reduction of METHEMOGLOBIN. The membrane-bound form of the enzyme is found primarily in the ENDOPLASMIC RETICULUM and outer mitochondrial membrane, where it participates in the desaturation of FATTY ACIDS; CHOLESTEROL biosynthesis and drug metabolism. A deficiency in the enzyme can result in METHEMOGLOBINEMIA.	Methemoglobin Reductase,NADH Cytochrome B5 Reductase,NADH Methemoglobin Reductase,NADH-Cytochrome B5 Reductase,NADH-Ferrihemoglobin Reductase,B5 Reductase, NADH-Cytochrome,Methemoglobin Reductase, NADH,NADH Ferrihemoglobin Reductase,Reductase, Methemoglobin,Reductase, NADH Methemoglobin,Reductase, NADH-Ferrihemoglobin