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SulfatasesSteryl-Sulfatase: An arylsulfatase with high specificity towards sulfated steroids. Defects in this enzyme are the cause of ICHTHYOSIS, X-LINKED.Iduronate Sulfatase: An enzyme that specifically cleaves the ester sulfate of iduronic acid. Its deficiency has been demonstrated in Hunter's syndrome, which is characterized by an excess of dermatan sulfate and heparan sulfate. EC 3.1.6.13.Chondro-4-Sulfatase: An enzyme from the sulfuric ester hydrolase class that breaks down one of the products of the chondroitin lyase II reaction. EC 3.1.6.9.Arylsulfatases: Enzymes that catalyze the hydrolysis of a phenol sulfate to yield a phenol and sulfate. Arylsulfatase A, B, and C have been separated. A deficiency of arylsulfatases is one of the causes of metachromatic leukodystrophy (LEUKODYSTROPHY, METACHROMATIC). EC 3.1.6.1.N-Acetylgalactosamine-4-Sulfatase: An arylsulfatase that catalyzes the hydrolysis of the 4-sulfate groups of the N-acetyl-D-galactosamine 4-sulfate units of chondroitin sulfate and dermatan sulfate. A deficiency of this enzyme is responsible for the inherited lysosomal disease, Maroteaux-Lamy syndrome (MUCOPOLYSACCHARIDOSIS VI). EC 3.1.6.12.Chondroitinsulfatases: A group of enzymes that catalyze the hydrolysis of various sulfate bonds of chondroitin sulfate. EC 3.1.6.-.Mucopolysaccharidosis II: Systemic lysosomal storage disease marked by progressive physical deterioration and caused by a deficiency of L-sulfoiduronate sulfatase. This disease differs from MUCOPOLYSACCHARIDOSIS I by slower progression, lack of corneal clouding, and X-linked rather than autosomal recessive inheritance. The mild form produces near-normal intelligence and life span. The severe form usually causes death by age 15.Multiple Sulfatase Deficiency Disease: An inherited metabolic disorder characterized by the intralysosomal accumulation of sulfur-containing lipids (sulfatides) and MUCOPOLYSACCHARIDES. Excess levels of both substrates are present in urine. This is a disorder of multiple sulfatase (arylsulfatases A, B, and C) deficiency which is caused by the mutation of sulfatase-modifying factor-1. Neurological deterioration is rapid.Ichthyosis, X-Linked: Chronic form of ichthyosis that is inherited as a sex-linked recessive trait carried on the X-chromosome and transmitted to the male offspring. It is characterized by severe scaling, especially on the extremities, and is associated with steroid sulfatase deficiency.Cerebroside-Sulfatase: An enzyme that catalyzes the hydrolysis of cerebroside 3-sulfate (sulfatide) to yield a cerebroside and inorganic sulfate. A marked deficiency of arylsulfatase A, which is considered the heat-labile component of cerebroside sulfatase, has been demonstrated in all forms of metachromatic leukodystrophy (LEUKODYSTROPHY, METACHROMATIC). EC 3.1.6.8.Mucopolysaccharidosis IV: Genetic disorder of mucopolysaccharide metabolism characterized by skeletal abnormalities, joint instability, development of cervical myelopathy, and excessive urinary keratan sulfate. There are two biochemically distinct forms, each due to a deficiency of a different enzyme.Ichthyosis: Any of several generalized skin disorders characterized by dryness, roughness, and scaliness, due to hypertrophy of the stratum corneum epidermis. Most are genetic, but some are acquired, developing in association with other systemic disease or genetic syndrome.Sulfotransferases: Enzymes which transfer sulfate groups to various acceptor molecules. They are involved in posttranslational sulfation of proteins and sulfate conjugation of exogenous chemicals and bile acids. EC 2.8.2.Mucopolysaccharidosis VI: Mucopolysaccharidosis with excessive CHONDROITIN SULFATE B in urine, characterized by dwarfism and deafness. It is caused by a deficiency of N-ACETYLGALACTOSAMINE-4-SULFATASE (arylsulfatase B).Leukodystrophy, Metachromatic: An autosomal recessive metabolic disease caused by a deficiency of CEREBROSIDE-SULFATASE leading to intralysosomal accumulation of cerebroside sulfate (SULFOGLYCOSPHINGOLIPIDS) in the nervous system and other organs. Pathological features include diffuse demyelination, and metachromatically-staining granules in many cell types such as the GLIAL CELLS. There are several allelic and nonallelic forms with a variety of neurological symptoms.Sphingolipidoses: A group of inherited metabolic disorders characterized by the intralysosomal accumulation of SPHINGOLIPIDS primarily in the CENTRAL NERVOUS SYSTEM and to a variable degree in the visceral organs. They are classified by the enzyme defect in the degradation pathway and the substrate accumulation (or storage). Clinical features vary in subtypes but neurodegeneration is a common sign.Estrone: An aromatized C18 steroid with a 3-hydroxyl group and a 17-ketone, a major mammalian estrogen. It is converted from ANDROSTENEDIONE directly, or from TESTOSTERONE via ESTRADIOL. In humans, it is produced primarily by the cyclic ovaries, PLACENTA, and the ADIPOSE TISSUE of men and postmenopausal women.Sulfonic Acids: Inorganic or organic oxy acids of sulfur which contain the RSO2(OH) radical.Mucopolysaccharidoses: Group of lysosomal storage diseases each caused by an inherited deficiency of an enzyme involved in the degradation of glycosaminoglycans (mucopolysaccharides). The diseases are progressive and often display a wide spectrum of clinical severity within one enzyme deficiency.Ichthyosis Vulgaris: Most common form of ICHTHYOSIS characterized by prominent scaling especially on the exterior surfaces of the extremities. It is inherited as an autosomal dominant trait.17-Hydroxysteroid Dehydrogenases: A class of enzymes that catalyzes the oxidation of 17-hydroxysteroids to 17-ketosteroids. EC 1.1.-.Lysosomal Storage Diseases: Inborn errors of metabolism characterized by defects in specific lysosomal hydrolases and resulting in intracellular accumulation of unmetabolized substrates.Mucopolysaccharidosis III: Mucopolysaccharidosis characterized by heparitin sulfate in the urine, progressive mental retardation, mild dwarfism, and other skeletal disorders. There are four clinically indistinguishable but biochemically distinct forms, each due to a deficiency of a different enzyme.Sulfates: Inorganic salts of sulfuric acid.Coumarins: Synthetic or naturally occurring substances related to coumarin, the delta-lactone of coumarinic acid.X Chromosome: The female sex chromosome, being the differential sex chromosome carried by half the male gametes and all female gametes in human and other male-heterogametic species.Dehydroepiandrosterone Sulfate: The circulating form of a major C19 steroid produced primarily by the ADRENAL CORTEX. DHEA sulfate serves as a precursor for TESTOSTERONE; ANDROSTENEDIONE; ESTRADIOL; and ESTRONE.Dydrogesterone: A synthetic progestational hormone with no androgenic or estrogenic properties. Unlike many other progestational compounds, dydrogesterone produces no increase in temperature and does not inhibit OVULATION.Lysosomes: A class of morphologically heterogeneous cytoplasmic particles in animal and plant tissues characterized by their content of hydrolytic enzymes and the structure-linked latency of these enzymes. The intracellular functions of lysosomes depend on their lytic potential. The single unit membrane of the lysosome acts as a barrier between the enzymes enclosed in the lysosome and the external substrate. The activity of the enzymes contained in lysosomes is limited or nil unless the vesicle in which they are enclosed is ruptured. Such rupture is supposed to be under metabolic (hormonal) control. (From Rieger et al., Glossary of Genetics: Classical and Molecular, 5th ed)Peptococcus: A genus of gram-positive, anaerobic, coccoid bacteria that is part of the normal flora of the mouth, upper respiratory tract, and large intestine in humans. Its organisms cause infections of soft tissues and bacteremias.Chondroitinases and Chondroitin Lyases: Enzymes which catalyze the elimination of glucuronate residues from chondroitin A,B, and C or which catalyze the hydrolysis of sulfate groups of the 2-acetamido-2-deoxy-D-galactose 6-sulfate units of chondroitin sulfate. EC 4.2.2.-.Glycosaminoglycans: Heteropolysaccharides which contain an N-acetylated hexosamine in a characteristic repeating disaccharide unit. The repeating structure of each disaccharide involves alternate 1,4- and 1,3-linkages consisting of either N-acetylglucosamine or N-acetylgalactosamine.Enzyme Replacement Therapy: Therapeutic replacement or supplementation of defective or missing enzymes to alleviate the effects of enzyme deficiency (e.g., GLUCOSYLCERAMIDASE replacement for GAUCHER DISEASE).Chondrodysplasia Punctata: A heterogeneous group of bone dysplasias, the common character of which is stippling of the epiphyses in infancy. The group includes a severe autosomal recessive form (CHONDRODYSPLASIA PUNCTATA, RHIZOMELIC), an autosomal dominant form (Conradi-Hunermann syndrome), and a milder X-linked form. Metabolic defects associated with impaired peroxisomes are present only in the rhizomelic form.Azasteroids: Steroidal compounds in which one or more carbon atoms in the steroid ring system have been substituted with nitrogen atoms.Aromatase: An enzyme that catalyzes the desaturation (aromatization) of the ring A of C19 androgens and converts them to C18 estrogens. In this process, the 19-methyl is removed. This enzyme is membrane-bound, located in the endoplasmic reticulum of estrogen-producing cells of ovaries, placenta, testes, adipose, and brain tissues. Aromatase is encoded by the CYP19 gene, and functions in complex with NADPH-FERRIHEMOPROTEIN REDUCTASE in the cytochrome P-450 system.Prevotella: A genus of gram-negative, anaerobic, nonsporeforming, nonmotile rods. Organisms of this genus had originally been classified as members of the BACTEROIDES genus but overwhelming biochemical and chemical findings in 1990 indicated the need to separate them from other Bacteroides species, and hence, this new genus was established.DiazomethaneFibroblasts: Connective tissue cells which secrete an extracellular matrix rich in collagen and other macromolecules.Sex Chromosome Aberrations: Abnormal number or structure of the SEX CHROMOSOMES. Some sex chromosome aberrations are associated with SEX CHROMOSOME DISORDERS and SEX CHROMOSOME DISORDERS OF SEX DEVELOPMENT.Norpregnadienes: Pregnadienes which have undergone ring contractions or are lacking carbon-18 or carbon-19.Dermatan Sulfate: A naturally occurring glycosaminoglycan found mostly in the skin and in connective tissue. It differs from CHONDROITIN SULFATE A (see CHONDROITIN SULFATES) by containing IDURONIC ACID in place of glucuronic acid, its epimer, at carbon atom 5. (from Merck, 12th ed)Hydrolases: Any member of the class of enzymes that catalyze the cleavage of the substrate and the addition of water to the resulting molecules, e.g., ESTERASES, glycosidases (GLYCOSIDE HYDROLASES), lipases, NUCLEOTIDASES, peptidases (PEPTIDE HYDROLASES), and phosphatases (PHOSPHORIC MONOESTER HYDROLASES). EC 3.Dehydroepiandrosterone: A major C19 steroid produced by the ADRENAL CORTEX. It is also produced in small quantities in the TESTIS and the OVARY. Dehydroepiandrosterone (DHEA) can be converted to TESTOSTERONE; ANDROSTENEDIONE; ESTRADIOL; and ESTRONE. Most of DHEA is sulfated (DEHYDROEPIANDROSTERONE SULFATE) before secretion.Chondroitin Lyases: Enzymes which catalyze the elimination of delta-4,5-D-glucuronate residues from polysaccharides containing 1,4-beta-hexosaminyl and 1,3-beta-D-glucuronosyl or 1,3-alpha-L-iduronosyl linkages thereby bringing about depolymerization. EC 4.2.2.4 acts on chondroitin sulfate A and C as well as on dermatan sulfate and slowly on hyaluronate. EC 4.2.2.5 acts on chondroitin sulfate A and C.Neoplasms, Hormone-Dependent: Certain tumors that 1, arise in organs that are normally dependent on specific hormones and 2, are stimulated or caused to regress by manipulation of the endocrine environment.Chondroitin Sulfates: Derivatives of chondroitin which have a sulfate moiety esterified to the galactosamine moiety of chondroitin. Chondroitin sulfate A, or chondroitin 4-sulfate, and chondroitin sulfate C, or chondroitin 6-sulfate, have the sulfate esterified in the 4- and 6-positions, respectively. Chondroitin sulfate B (beta heparin; DERMATAN SULFATE) is a misnomer and this compound is not a true chondroitin sulfate.Sulfuric Acid Esters: Organic esters of sulfuric acid.Hybrid Cells: Any cell, other than a ZYGOTE, that contains elements (such as NUCLEI and CYTOPLASM) from two or more different cells, usually produced by artificial CELL FUSION.Tyramine: An indirect sympathomimetic. Tyramine does not directly activate adrenergic receptors, but it can serve as a substrate for adrenergic uptake systems and monoamine oxidase so it prolongs the actions of adrenergic transmitters. It also provokes transmitter release from adrenergic terminals. Tyramine may be a neurotransmitter in some invertebrate nervous systems.Megestrol: 17-Hydroxy-6-methylpregna-3,6-diene-3,20-dione. A progestational hormone used most commonly as the acetate ester. As the acetate, it is more potent than progesterone both as a progestagen and as an ovulation inhibitor. It has also been used in the palliative treatment of breast cancer.Sex Chromosomes: The homologous chromosomes that are dissimilar in the heterogametic sex. There are the X CHROMOSOME, the Y CHROMOSOME, and the W, Z chromosomes (in animals in which the female is the heterogametic sex (the silkworm moth Bombyx mori, for example)). In such cases the W chromosome is the female-determining and the male is ZZ. (From King & Stansfield, A Dictionary of Genetics, 4th ed)GlucuronidaseSulfuric Acids: Inorganic and organic derivatives of sulfuric acid (H2SO4). The salts and esters of sulfuric acid are known as SULFATES and SULFURIC ACID ESTERS respectively.Heparitin Sulfate: A heteropolysaccharide that is similar in structure to HEPARIN. It accumulates in individuals with MUCOPOLYSACCHARIDOSIS.Molecular Sequence Data: Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.Placenta: A highly vascularized mammalian fetal-maternal organ and major site of transport of oxygen, nutrients, and fetal waste products. It includes a fetal portion (CHORIONIC VILLI) derived from TROPHOBLASTS and a maternal portion (DECIDUA) derived from the uterine ENDOMETRIUM. The placenta produces an array of steroid, protein and peptide hormones (PLACENTAL HORMONES).Dosage Compensation, Genetic: Genetic mechanisms that allow GENES to be expressed at a similar level irrespective of their GENE DOSAGE. This term is usually used in discussing genes that lie on the SEX CHROMOSOMES. Because the sex chromosomes are only partially homologous, there is a different copy number, i.e., dosage, of these genes in males vs. females. In DROSOPHILA, dosage compensation is accomplished by hypertranscription of genes located on the X CHROMOSOME. In mammals, dosage compensation of X chromosome genes is accomplished by random X CHROMOSOME INACTIVATION of one of the two X chromosomes in the female.Clinical Enzyme Tests: Analyses for a specific enzyme activity, or of the level of a specific enzyme that is used to assess health and disease risk, for early detection of disease or disease prediction, diagnosis, and change in disease status.Bacteroides: A genus of gram-negative, anaerobic, rod-shaped bacteria. Its organisms are normal inhabitants of the oral, respiratory, intestinal, and urogenital cavities of humans, animals, and insects. Some species may be pathogenic.Pregnenolone: A 21-carbon steroid, derived from CHOLESTEROL and found in steroid hormone-producing tissues. Pregnenolone is the precursor to GONADAL STEROID HORMONES and the adrenal CORTICOSTEROIDS.Food Additives: Substances which are of little or no nutritive value, but are used in the processing or storage of foods or animal feed, especially in the developed countries; includes ANTIOXIDANTS; FOOD PRESERVATIVES; FOOD COLORING AGENTS; FLAVORING AGENTS; ANTI-INFECTIVE AGENTS (both plain and LOCAL); VEHICLES; EXCIPIENTS and other similarly used substances. Many of the same substances are PHARMACEUTIC AIDS when added to pharmaceuticals rather than to foods.Borohydrides: A class of inorganic or organic compounds that contain the borohydride (BH4-) anion.Estrogens: Compounds that interact with ESTROGEN RECEPTORS in target tissues to bring about the effects similar to those of ESTRADIOL. Estrogens stimulate the female reproductive organs, and the development of secondary female SEX CHARACTERISTICS. Estrogenic chemicals include natural, synthetic, steroidal, or non-steroidal compounds.Hexosaminidases: Enzymes that catalyze the hydrolysis of N-acylhexosamine residues in N-acylhexosamides. Hexosaminidases also act on GLUCOSIDES; GALACTOSIDES; and several OLIGOSACCHARIDES.Substrate Specificity: A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.Glycine: A non-essential amino acid. It is found primarily in gelatin and silk fibroin and used therapeutically as a nutrient. It is also a fast inhibitory neurotransmitter.Kinetics: The rate dynamics in chemical or physical systems.Alanine: A non-essential amino acid that occurs in high levels in its free state in plasma. It is produced from pyruvate by transamination. It is involved in sugar and acid metabolism, increases IMMUNITY, and provides energy for muscle tissue, BRAIN, and the CENTRAL NERVOUS SYSTEM.Cells, Cultured: Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.Catalytic Domain: The region of an enzyme that interacts with its substrate to cause the enzymatic reaction.Estradiol: The 17-beta-isomer of estradiol, an aromatized C18 steroid with hydroxyl group at 3-beta- and 17-beta-position. Estradiol-17-beta is the most potent form of mammalian estrogenic steroids.Cysteine: A thiol-containing non-essential amino acid that is oxidized to form CYSTINE.Keratan Sulfate: A sulfated mucopolysaccharide initially isolated from bovine cornea. At least two types are known. Type I, found mostly in the cornea, contains D-galactose and D-glucosamine-6-O-sulfate as the repeating unit; type II, found in skeletal tissues, contains D-galactose and D-galactosamine-6-O-sulfate as the repeating unit.Y Chromosome: The male sex chromosome, being the differential sex chromosome carried by half the male gametes and none of the female gametes in humans and in some other male-heterogametic species in which the homologue of the X chromosome has been retained.Genetic Linkage: The co-inheritance of two or more non-allelic GENES due to their being located more or less closely on the same CHROMOSOME.Chromatography, Liquid: Chromatographic techniques in which the mobile phase is a liquid.Metabolism, Inborn Errors: Errors in metabolic processes resulting from inborn genetic mutations that are inherited or acquired in utero.Sulfonamides: A group of compounds that contain the structure SO2NH2.Hydrolysis: The process of cleaving a chemical compound by the addition of a molecule of water.Protein Processing, Post-Translational: Any of various enzymatically catalyzed post-translational modifications of PEPTIDES or PROTEINS in the cell of origin. These modifications include carboxylation; HYDROXYLATION; ACETYLATION; PHOSPHORYLATION; METHYLATION; GLYCOSYLATION; ubiquitination; oxidation; proteolysis; and crosslinking and result in changes in molecular weight and electrophoretic motility.Mutation: Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.Heparan Sulfate Proteoglycans: Ubiquitous macromolecules associated with the cell surface and extracellular matrix of a wide range of cells of vertebrate and invertebrate tissues. They are essential cofactors in cell-matrix adhesion processes, in cell-cell recognition systems, and in receptor-growth factor interactions. (From Cancer Metastasis Rev 1996; 15(2): 177-86; Hepatology 1996; 24(3): 524-32)Mosaicism: The occurrence in an individual of two or more cell populations of different chromosomal constitutions, derived from a single ZYGOTE, as opposed to CHIMERISM in which the different cell populations are derived from more than one zygote.Amino Acid Sequence: The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.Chromatography, High Pressure Liquid: Liquid chromatographic techniques which feature high inlet pressures, high sensitivity, and high speed.Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.Breast Neoplasms: Tumors or cancer of the human BREAST.Alopecia: Absence of hair from areas where it is normally present.Point Mutation: A mutation caused by the substitution of one nucleotide for another. This results in the DNA molecule having a change in a single base pair.Phenotype: The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.RNA, Messenger: RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.Pseudomonas: A genus of gram-negative, aerobic, rod-shaped bacteria widely distributed in nature. Some species are pathogenic for humans, animals, and plants.Recombinant Proteins: Proteins prepared by recombinant DNA technology.Skin: The outer covering of the body that protects it from the environment. It is composed of the DERMIS and the EPIDERMIS.Microsomes: Artifactual vesicles formed from the endoplasmic reticulum when cells are disrupted. They are isolated by differential centrifugation and are composed of three structural features: rough vesicles, smooth vesicles, and ribosomes. Numerous enzyme activities are associated with the microsomal fraction. (Glick, Glossary of Biochemistry and Molecular Biology, 1990; from Rieger et al., Glossary of Genetics: Classical and Molecular, 5th ed)Carcinoma, Endometrioid: An adenocarcinoma characterized by the presence of cells resembling the glandular cells of the ENDOMETRIUM. It is a common histological type of ovarian CARCINOMA and ENDOMETRIAL CARCINOMA. There is a high frequency of co-occurrence of this form of adenocarcinoma in both tissues.Enzyme Inhibitors: Compounds or agents that combine with an enzyme in such a manner as to prevent the normal substrate-enzyme combination and the catalytic reaction.Sequence Homology, Amino Acid: The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.Hydrogen-Ion Concentration: The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH = log 1/2[1/(H+)], where (H+) is the hydrogen ion concentration in gram equivalents per liter of solution. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Heparin: A highly acidic mucopolysaccharide formed of equal parts of sulfated D-glucosamine and D-glucuronic acid with sulfaminic bridges. The molecular weight ranges from six to twenty thousand. Heparin occurs in and is obtained from liver, lung, mast cells, etc., of vertebrates. Its function is unknown, but it is used to prevent blood clotting in vivo and vitro, in the form of many different salts.Leukocytes: White blood cells. These include granular leukocytes (BASOPHILS; EOSINOPHILS; and NEUTROPHILS) as well as non-granular leukocytes (LYMPHOCYTES and MONOCYTES).Gene Expression Regulation, Enzymologic: Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control of gene action in enzyme synthesis.GlucosamineSerine: A non-essential amino acid occurring in natural form as the L-isomer. It is synthesized from GLYCINE or THREONINE. It is involved in the biosynthesis of PURINES; PYRIMIDINES; and other amino acids.Glycoside HydrolasesCarrageenan: A water-soluble extractive mixture of sulfated polysaccharides from RED ALGAE. Chief sources are the Irish moss CHONDRUS CRISPUS (Carrageen), and Gigartina stellata. It is used as a stabilizer, for suspending COCOA in chocolate manufacture, and to clarify BEVERAGES.Cell Line: Established cell cultures that have the potential to propagate indefinitely.Genes: A category of nucleic acid sequences that function as units of heredity and which code for the basic instructions for the development, reproduction, and maintenance of organisms.Gene Deletion: A genetic rearrangement through loss of segments of DNA or RNA, bringing sequences which are normally separated into close proximity. This deletion may be detected using cytogenetic techniques and can also be inferred from the phenotype, indicating a deletion at one specific locus.Isoelectric Focusing: Electrophoresis in which a pH gradient is established in a gel medium and proteins migrate until they reach the site (or focus) at which the pH is equal to their isoelectric point.Chromosome Mapping: Any method used for determining the location of and relative distances between genes on a chromosome.Oligosaccharides: Carbohydrates consisting of between two (DISACCHARIDES) and ten MONOSACCHARIDES connected by either an alpha- or beta-glycosidic link. They are found throughout nature in both the free and bound form.Liver: A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.Heterozygote: An individual having different alleles at one or more loci regarding a specific character.Transfection: The uptake of naked or purified DNA by CELLS, usually meaning the process as it occurs in eukaryotic cells. It is analogous to bacterial transformation (TRANSFORMATION, BACTERIAL) and both are routinely employed in GENE TRANSFER TECHNIQUES.