Download list of DEFINITIONS

list of DEFINITIONS
D
A. Kruit: definitions
Allele - Any one of a number of alternative forms of the same gene occupying
a given locus (position) on a chromosome.
Chromosome - A large macromolecule which carries densely packed genetic
information in biological cells.
Disease phenotype - A specific manifestation of a disorder or structure in a
human in terms of clinical characteristics.
Epistasis - The control of a phenotype by two or more genes.
Exon - The coding DNA region in a gene.
Gene - The DNA that encodes the chemical structure of a protein.
Gene polymorphism - A DNA sequence variation, occurring when a single
nucleotide in the genome is altered.
Genome - The whole hereditary information of an organism that is encoded in
the DNA. This includes both the genes and the non-coding sequences.
Genotype - The specific genetic makeup (the specific genome) of an
individual, usually in the form of DNA. It codes for the phenotype of that
individual.
Haplotype - A set of single nucleotide polymorphisms (SNPs) found to be
statistically associated on a single chromatid.
Heterozygous - An organism carrying two different versions of a gene on the
two corresponding chromosomes.
Homozygous - An organism carrying identical versions of a gene on the two
corresponding chromosomes.
Intron - The non-coding DNA region in a gene that is spliced out in the
process of translation.
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definitions
Linkage disequilibrium (LD) - The non-random association of alleles at two or
more loci on a chromosome. It describes a situation in which some
combinations of alleles or genetic markers occur more or less frequently in a
population than would be expected from their distance.
Locus (plural: loci) - The position of a gene (or other significant sequence) on a
chromosome. A locus can be occupied by any of the alleles of the gene.
Primer - A short DNA strand (or related molecule) that serves as a starting
point for DNA replication.
Quantitative trait locus (QTL) - A region of DNA that is associated with a
particular trait (e.g., biomarker levels). Though not necessarily genes
themselves, QTLs are stretches of DNA that are closely linked to the genes that
underlie the trait in question.
Reference interval - The range of values (usually 95% confidence limits) found
in an apparently healthy population (i.e, not afflicted by an illness).
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