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| F - Z |
Familial adenomatous polyposis:
an inherited condition in which hundreds of potentially
cancerous polyps develop in the colon and rectum.
cancer, or a predisposition toward cancer, that runs
a unit of inheritance; a working subunit of DNA. Each
of the body's 50,000 to 100,000 genes contains the code
for a specific product, typically, a protein such as
the total loss or absence of a gene.
the process by which a gene's coded information is
translated into the structures present and operating
in the cell (either proteins or RNAs).
landmarks for a target gene, either detectable traits
that are inherited along with the gene, or distinctive
segments of DNA.
determining the relative positions of genes on a chromosome
and the distance between them.
examining a sample of blood or other body fluid or
tissue for biochemical, chromosomal, or genetic markers
that indicate the presence or absence of genetic disease.
treating disease by replacing, manipulating, or supplementing
Genetic linkage maps:
DNA maps that assign relative chromosomal locations
to genetic landmarks?ither genes for known traits or
distinctive sequences of DNA - on the basis of how frequently
they are inherited together. (See Physical maps.)
the scientific study of heredity: how particular qualities
or traits are transmitted from parents to offspring.
all the genetic material in the chromosomes of a particular
charts that indicate the ordered arrangement of the
genes or other DNA markers within the chromosomes.
the actual genes carried by an individual (as distinct
from phenotype?hat is, the physical characteristics
into which genes are translated).
the reproductive cells of the body, either egg or sperm
(See Hereditary mutation.)
a gene change in the body's reproductive cells (egg
or sperm) that becomes incorporated in the DNA of every
cell in the body; also called germline mutation. (See
the full collection of genes needed to produce a human
Human Genome Project:
an international research effort (led in the United
States by the National Institutes of Health and the
Department of Energy) aimed at identifying and ordering
every base in the human genome.
an adult-onset disease characterized by progressive
mental and physical deterioration; it is caused by an
inherited dominant gene mutation.
a biochemical phenomenon that determines, for certain
genes, which one of the pair of alleles, the mother's
or the father's, will be active in that individual.
Inborn errors of metabolism:
inherited diseases resulting from alterations in genes
that code for enzymes.
cancer that begins in developing blood cells in the
a family predisposition to multiple cancers, caused
by a mutation in the p53 tumor-suppressor gene.
a gene-hunting technique that traces patterns of heredity
in large, high-risk families, in an attempt to locate
a disease-causing gene mutation by identifying traits
that are co-inherited with it.
a cancer that begins in skin cells called melanocytes
and spreads to internal organs.
a group of atoms arranged to interact in a particular
way; one molecule of any substance is the smallest physical
unit of that particular substance.
a change in the number, arrangement, or molecular sequence
of a gene.
examining blood samples from a newborn infant to detect
disease-related abnormalities or deficiencies in gene
A subunit of DNA or RNA, consisting of one chemical
base plus a phosphate molecule and a sugar molecule.
the cell structure that houses the chromosomes.
genes that normally play a role in the growth of cells
but, when overexpressed or mutated, can foster the growth
(See Tumor-suppressor genes.)
a term indicating the likelihood that a given gene
will actually result in disease.
an inborn error of metabolism caused by the lack of
an enzyme, resulting in abnormally high levels of the
amino acid phenylalanine; untreated, PKU can lead to
severe, progressive mental retardation.
DNA maps showing the location of identifiable landmarks,
either genes or distinctive short sequences of DNA.
The lowest resolution physical map shows the banding
pattern on the 24 different chromosomes; the highest
resolution map depicts the complete nucleotide sequence
of the chromosomes. (See Contig maps.)
growths in the colon that often become cancerous.
Predictive gene tests:
tests to identify gene abnormalities that may make
a person susceptible to certain diseases or disorders.
examining fetal cells taken from the amniotic fluid,
the primitive placenta (chorion), or the umbilical cord
for biochemical, chromosomal, or gene alterations.
a specific sequence of single-stranded DNA, typically
labeled with a radioactive atom, which is designed to
bind to, and thereby single out, a particular segment
(See DNA repair genes.)
surgery to remove tissue that is in danger of becoming
cancerous, before cancer has the chance to develop.
Surgery to remove the breasts of women at high risk
of developing breast cancer is known as prophylactic
a large, complex molecule composed of amino acids.
The sequence of the amino acids?nd thus the function
of the protein?s determined by the sequence of the base
pairs in the gene that encodes it. Proteins are essential
to the structure, function, and regulation of the body.
Examples are hormones, enzymes, and antibodies.
the protein molecule assembled under the direction
of a gene.
a gene that is expressed only when its counterpart
allele on the matching chromosome is also recessive
(not dominant). Autosomal recessive disorders develop
in persons who receive two copies of the mutant gene,
one from each parent who is a carrier. (See Dominant
(See Crossing over.)
Renal cell cancer:
a type of kidney cancer.
egg and sperm cells. Each mature reproductive cell
carries a single set of 23 chromosomes.
enzymes that can cut strands of DNA at specific base
an eye cancer caused by the loss of a pair of tumor-suppressor
genes; the inherited form typically appears in childhood,
since one gene is missing from the time of birth.
a chemical similar to DNA. The several classes of RNA
molecules play important roles in protein synthesis
and other cell activities.
a type of cancer that starts in bone or muscle.
looking for evidence of a particular disease such as
cancer in persons with no symptoms of disease.
the chromosomes that determine the sex of an organism.
Human females have two X chromosomes; males have one
X and one Y.
an inherited, potentially lethal disease in which a
defect in hemoglobin, the oxygen-carrying pigment in
the blood, causes distortion (sickling) and loss of
red blood cells, producing damage to organs throughout
all body cells except the reproductive cells.
(See Acquired mutations.)
an inherited disease of infancy characterized by profound
mental retardation and early death; it is caused by
a recessive gene mutation.
the process of copying information from DNA into new
strands of messenger RNA (mRNA). The mRNA then carries
this information to the cytoplasm, where it serves as
the blueprint for the manufacture of a specific protein.
the process of turning instructions from mRNA, base
by base, into chains of amino acids that then fold into
proteins. This process takes place in the cytoplasm,
on structures called ribosomes.
genes that normally restrain cell growth but, when
missing or inactivated by mutation, allow cells to grow
a kidney cancer (tumor) that occurs in children, usually
before age 5.
a sex chromosome; normal females carry two X chromosomes.
a sex chromosome; normal males carry one Y and one