Ask a Medical Question
GlossaryGlossary
A | B | C | D | E | F | G | H | I | J | K | L | M
N | O | P | Q | R | S | T | U | V | W | X | Y | Z
Acid alpha-glucosidase (GAA)
An enzyme responsible for the breakdown of glycogen (a large complex carbohydrate molecule) within a compartment of the cell known as the lysosome. Pompe disease is caused by an inherited deficiency or dysfunction of acid alpha-glucosidase (GAA).
Acid maltase deficiency (AMD)
Alanine aminotransferase (ALT)
A liver enzyme that when present in abnormally high levels in the blood, it may be an indication of a heart attack or liver problems.
Allele
One or more alternate forms of a gene that occupies a single location (also known as a locus) on a chromosome. For example, the gene for blue eye color and gene for brown eye color are two alleles of the gene for eye color.
Amniocentesis
Withdrawal of fluid from the amniotic sac, the innermost membrane surrounding the fetus containing amniotic fluid.
Areflexia
Aspartate aminotransferase (AST)
A liver enzyme that when present in abnormally high levels in the blood, it may be an indication of a heart attack or liver problems.
Autosomal recessive disease
Autosomal recessive diseases are genetic disorders passed from parent to child only when the child inherits two abnormal copies of a gene, one from each parent.
Bilevel positive airway pressure (BiPAP)
Bilevel positive airway pressure (BiPAP) is a modified version of the continuous positive airway pressure (CPAP). This mode offers two different levels of air pressure: increased pressure during inhalation and decreased pressure during exhalation. BiPAPs may work better for those individuals who cannot comfortably breathe out against the fixed pressure of the standard device.
Biventricular hypertrophy
Enlargement or overgrowth of both the right and left ventricles, the heart's two lower chambers.
Cardiomegaly
Carrier
An individual who does not display the symptoms of a disease, but carries the gene (or genes) for it. A carrier can transmit the disease by passing the abnormal gene (or genes) to offspring. Synonym of heterozygote.
Chorionic villi
Tiny membrane projections in the developing placenta (the tissue that connects the umbilical cord to the uterus). A procedure called chorionic villus sampling obtains chorionic villi cells for the purpose of prenatal testing, which can be performed as early as the 12th week of pregnancy.
Chromosome
The self-replicating genetic structures of cells that contain cellular DNA (the molecule that encodes genetic information). Chromosomes come in pairs, and a normal human cell contains 46 chromosomes.
Congenital
Existing at birth, referring to certain mental or physical traits, malformations, or diseases, which may be hereditary or due to an influence occurring during gestation (in utero).
Continuous positive airway pressure (CPAP)
CPAP ventilators provide positive pressure that is constant when a patient inhales and exhales. This can require more work for the muscles to exhale. For people with Pompe disease, the CPAP machine is generally used to treat sleep apnea (when breathing stops for short periods during sleep).
Creatine kinase (CK)
Creatine kinase (CK) is an enzyme found in muscle, brain, and other tissues. CK is released in increased quantities when muscle injury occurs.
Deoxyribonucleic acid (DNA)
The molecule that carries the genetic instructions for making living organisms. Located in the nucleus of a cell, the DNA molecule determines the structure, function and behavior of the cell.
Enzyme
A protein that triggers or "catalyzes" a biochemical reaction.
Exertional dyspnea
Excessive shortness of breath after exercise.
"Floppy baby" syndrome
An abnormal condition of newborns and infants where there is inadequate tone of the muscles.
Gene
The functional and physical unit of heredity that occupies a specific location (locus) on a chromosome. Formed from DNA, genes are passed from parent to offspring and are responsible for the inherited characteristics that distinguish one individual from another.
Genetic counselor
A health care professional who has obtained training and credentials in the area of genetics and who provides information and support to families who may be at risk for a variety of inherited conditions.
Geneticist
A physician who specializes in genetics, the study of heredity and variation of organisms.
Genotype
The genetic make-up of an individual's cells. The genotype together with the biologic environment produce the phenotype, or the visible characteristic displayed.
Glycogen
A large, complex carbohydrate molecule stored in the liver and muscles. Glycogen releases glucose (sugar) into the blood when needed by cells, and is the chief source of stored fuel in the body.
Glycogen storage disease
A group of inherited metabolic disorders involving the enzymes responsible for the synthesis and breakdown of glycogen. There are several types of GSDs, which are classified by a number, by the name of the defective enzyme, or by the name of the doctor who first described the condition.
Glycogen storage disease type II (GSD-II)
Gower sign (aka Gowers maneuver)
(Commonly seen in children with muscular dystrophy as a result of extreme muscle weakness.) Gower sign refers to an abnormal method of attempting to stand up, in which the person begins with both arms and legs on the floor and then uses the arms to push against the legs and raise up the trunk to an upright posture. Sometimes described as "climbing up the legs."
Hepatomegaly
Heterozygote
An individual that has one normal copy and one abnormal copy of a specific gene. Also known as carrier.
Hypertrophy
The enlargement or overgrowth of a part or organ, not due to tumor formation. Hypertrophy denotes greater bulk through increase in size, but not in number, of cells or other individual tissue elements.
Hypotonia
A condition of diminished tone of the skeletal muscles, and the reduced resistance of muscles to passive stretching.
Lordosis
Exaggerated forward curvature of the lumbar and/or cervical areas of the spine.
Lysosomal storage disorder (LSD)
A group of more than 40 genetic diseases that are caused by inborn errors of metabolism and that result in the accumulation of various substances within a compartment of the cell known as the lysosome. People with LSDs are born with a deficiency or dysfunction of certain enzymes found within the lysosome. Synonym of lysosomal storage disorder.
Lysosome
A sac-like organelle (a structurally discrete component of a cell) that contains various digestive enzymes as well as acidic materials.
Macroglossia
Molecule
The smallest particle of a substance that retains all the properties of the substance and is composed of one or more atoms.
Mutation
A permanent transmissible change in genetic material, usually in a single gene.
Myopathy
Any disorder or disease of muscle tissue or muscles.
Neurologist
A physician who diagnoses and treats disorders of the central nervous system.
Neuromuscular disorder
A disorder involving the relationship between nerves and muscles, and especially the weakening or dysfunction of the muscles.
Orthopnea
The inability to breathe easily in a flat body position.
Phenotype
The visible characteristics (e.g. eye color) that are produced by the interaction of the genotype (the genetic constitution of an organism) and the biologic environment.
Physical therapist
A specialist trained in the treatment of diseases and injury through exercise and physical activities.
Polysomnography
The technique of monitoring normal and abnormal physiologic activity during sleep.
Pompe disease
A genetic disorder affecting both children and adults that is characterized by progressive muscle weakness and breathing difficulty. Pompe disease is caused by a deficiency or dysfunction of the enzyme acid alpha-glucosidase (GAA) that is responsible for the breakdown of glycogen (a large complex carbodhydrate molecule) within a compartment of the cell, resulting in an excessive accumulation of glycogen, especially in the muscles. Also known as glycogen storage disease type II (GSD-II) and acid maltase deficiency (AMD).
Protein
Any of a number of naturally occurring complex substances (such as enzymes or antibodies) involved in essential life functions.
Registered dietician
A professional who has obtained training and credentials related to the use of specialized diets to address a variety of problems.
Ribonucleic acid (RNA)
A nucleic acid that helps transfer information from DNA to the protein-forming system of the cell.
Scoliosis
An abnormal lateral curvature of the spine.
Somnolence
Tracheostomy
A surgical operation to create an opening into the trachea (windpipe).
Vacuolar
Relating to a vacuole, a small cavity or space containing air or fluid.
