Genetic screening: ethical issues - Nuffield Council on Bioethics

<strong>Genetic</strong> disease or disorder
Conditions which are the result of alterations in the genetic make-up of an individual.
They may be the direct consequences of defects in single genes (mutations); or in
whole chromosomes, parts of which may be lost, duplicated or misplaced; or from the
interaction of multiple genes and external factors.
<strong>Genetic</strong> fingerprinting
A technique which enables genetic relationships between close relatives, or the identity
of individuals to be established - usually beyond reasonable doubt.
<strong>Genetic</strong> map
The body of information on the relative positions of genes on chromosomes. Much
of the effort of the Human Genome Project is directed towards mapping
chromosomes.
<strong>Genetic</strong> marker
A harmless variable inherited change in DNA or protein that can be used to locate a
disease gene on a particular chromosome.
Genome
The total genetic complement of an individual, or of a species.
Haemoglobin
The oxygen-carrying protein found in mammalian red blood cells. Various gene
mutations can result in diseases called the haemoglobin disorders.
Multifactorial
A term which denotes that many factors, often environmental (such as diet and
smoking) contribute to the development of a disease. Often used interchangeably with
polygenic.
Mutation
A change in the structure of DNA, usually permanent and transmissible. Mutations
within genes are the cause of genetic disease.
Polygenic
Controlled by or associated with more than one gene.
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Polymerase chain reaction (PCR)
A laboratory process in which a specific DNA sequence is amplified many millions of
times in only a few hours.
Positional cloning
Isolation of a gene through knowledge of its specific location on a particular
chromosome.
Protein
A molecule composed of many amino acids, folded into a particular shape so that it
may form a specific function. There are many types of proteins, for example, enzymes
are proteins.