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Vocabulary Terms Sorted Alphabetically

Listed By Lesson



Activator: transcription factors that bind to an enhancer and increase transcriptional activity

Adenine (A): a type of nitrogenous base that is typically used in both DNA and RNA (A basepairs with U or T)

Allele: specific variant of a genetic sequence for which more than one variation exists, sometimes associated with a unique phenotype

Allele Frequency: the frequency of an allele is equal to the number of that allele divided by the total number of alleles in a given population

Amino Acid: the basic building blocks of proteins, combined by ribosomes during the process of translation; there are 20 different amino acids

Aneuploidy: a chromosomal aberration in which certain chromosomes are present in extra copies or are deficient in number

Autosome: a nuclear chromosome that is not a sex chromosome (X or Y)


Basepair: the phenomenon of nitrogenous bases in nucleic acid pairing with one another in double-stranded DNA or RNA, following the rules A:T, G:C in DNA and A:U, G:C in RNA

Behavioral Trait: any trait that concerns an organism's action or interaction with or within an environment, for example: agressiveness

Blending Inheritance: the idea that a particular trait in an offspring is a mix of the parents’ traitsv Bottleneck: genetic drift resulting from the reduction of a population, typically by a natural disaster, such that the surviving population is no longer genetically representative of the original population


Chromosome: a super-coiled structure of organized DNA wrapped around histones; contains a single molecule of DNA

Coding DNA: sometimes referred to as "protein-coding DNA"; refers to any sequence in the genome that specifies amino acids and translation signals (initiation and termination codons)

Codon: a three-nucleotide sequence of mRNA that specifies a particular amino acid or termination signal

Combinatorial Regulation: the idea that transcription of most genes is controlled by more than one activator or repressor to achieve a particular level of activity

Consensus Sequence: a single sequence that represents the most prevalent individual unit at each position, derived by comparing variants of the sequence from different sources

Cytochrome P450: a large and diverse group of enzymes that catalyze the oxidation (metabolism) of organic substances (drugs)

Cytoplasm: the interior of a cell, excluding the nucleus

Cytosine (C): a type of nitrogenous base that is typically used in both DNA and RNA (C basepairs with G)


Deoxynucleotide: the building blocks of DNA; there are four different bases used in deoxynucleotides: Adenine (A), Thymine (T), Guanine (G), and Cytosine (C)

Direct Selection: (see natural selection)

Dizygotic Twins: twins that came from two different fertilized eggs or zygotes; fraternal twins

DNA: deoxyribonucleic acid; the hereditary material of almost all cells that makes up their genomes

DNA Amplification: the in vitro replication of a DNA sequence to make many more copies

DNA Extraction: the isolation of DNA from a biological sample

DNA Sequence: a string of DNA letters (bases) in consecutive order

Dominant Trait: can mask the presence of a recessive allele or trait

Double Helix: the structure of DNA, referring to its two adjacent strands wound into a spiral shape and held together through basepairing

Duplicated Chromosome: the stereotypical structure in the shape of an "X" for a nuclear chromosome that appears only before cell division

Duplication: a replication error that doubles a large segment of DNA


Efficacy: a drug's ability to produce a therapeutic effect

Egg: female reproductive cell

Enhancer: a DNA sequence that binds certain transcription factors, activators, that can stimulate transcription of nearby genes

Enzyme: a class of proteins that enable chemical reactions without being consumed by the reaction

Exon: a sequence from a gene that is transcribed and remains in the mRNA after splicing and includes codes for amino acids


Founder Effect: a cause of genetic drift attributable to colonization by a limited number of individuals from a parent population

Frameshift: any mutation that results in changing the reading frame of translation


Gain-Of-Function Mutation: changes the gene product such that it gains a new and/or abnormal function

Gamete: sperm or egg cells; produce as a result of meiosis from germ cells

Gene: a discrete unit of hereditary informaiton consisting of a specific deoxynucleotide sequence in DNA

Gene Expression: the process by which information from a gene is used in the synthesis of a functional gene product

Genome: the complete complement of an organism's genetic material

Genome-Wide Association Study (GWAS): GWAS seek to correlate, in populations, the association of specific alleles with the trait or disorder being studied

Genotype: the genetic makeup of an organism, specifically the composition of alleles

Germ Cell: the type of the cell in the body that makes gametes; this is the only cell type where mutations affect the next generation of an organism

Guanine (G): a type of nitrogenous base that is typically used in both DNA and RNA (G basepairs with C)


Heritability: the proportion, between 0 and 1, of observable differences in variation of a trait between individuals within a population that is due to genetic differences

Heterozygote Advantage: describes the case in which the heterozygous genotype has a higher relative fitness than either the homozygous dominant or homozygous recessive genotype

Heterozygous: having two different alleles for a given gene

Hidden trait: any trait that is not apparent through outward observation

Histone: a protein that is used to organize and fold DNA like a string on a spool

Homozygous: having two identical alleles for a given gene

Hybridization: the process of basepairing that can occur between any types of nucleic acids (DNA:DNA, DNA:RNA, or RNA:RNA)


Identity By Descent (IBD): genetic sequence shared through ancestry

Identity By State (IBS): genetic sequence that is identical between two individuals

Inheritance: the passing down of traits from one generation to the next, at the level of the cell or the organism

Innate Trait: any trait that is in-born, for example: your pancreas secreting enzymes that break down the food in your gut

Intron: a sequence from a gene that is transcribed but cut out of the mRNA by splicing and typically does not code for any amino acids


Lactase Persistence: the continued activity of the enzyme lactase into adulthood

Lactose Intolerance: the inability to digest lactose that results in an array of symptoms largely including digestive discomfort, gas, and diarrhea

Learned Trait: any trait that is not in-born and instead acquired through environmental (typically cognitive) influence, for example: belief in a particular religion

Loss-Of-Function Mutation: results in the gene product having less or no function


Meiosis: a two-stage type of cell division in germ cells that results in gametes with half the chromosome number of the original cell

Missense/Non-Synonymous Mutation: a mutation that changes an amino acid

Mitochondrial DNA: a circular DNA molecule that can only be found in the mitochondria of all cells in the body and is inherited only from the mother

Mitosis: the normal chromosome doubling and division that all somatic (body) cells do to maintain the same number of chromosomes at the end of each division

Monogenic Trait: traits that are significantly influenced by a single gene

Monozygotic Twins: twins that came from the same fertilized egg or zygote; identical twins

Multifactorial Trait: a trait that is controlled by many genes and is also influenced by the environment

Mutation: a change in the genetic sequence


Natural Selection: the process by which traits become either more or less common in a population because of pressures directly affecting the reproductive fitness of individuals carrying particular alleles; also considered "direct selection" due to pressures that directly affect the fitness of particular alleles

Non-Coding DNA: any sequence that does not specify amino acids and translation signals (initiation and termination codons)

Non-Duplicated Chromosome: a non-"X"-shaped nuclear chromosome

Nonsense Mutation: a mutation that changes an amino acid codon to a STOP codon

Nuclear Genome: the complete set of 23 pairs of chromosomes that reside within the nucleus of the cell

Nucleotide: building block of DNA and RNA consisting of a base, a ribose or deoxyribose sugar and a phosphate group; there are four different bases used in nucleotides: Adenine (A), Thymine (T) in DNA or Uracil (U) in RNA, Guanine (G), and Cytosine (C)

Nucleus: a separate, membrane-bound compartment of eukaryotic cells that houses the DNA and separates it from the rest of the cell; this is where transcription occurs


Particulate Inheritance: the idea that characteristics can be passed down from generation to generation through discrete particles, i.e. genes

Pedigree: organized way of illustrating (drawing) family relations and traits

Personal Genome: the entirety of your own individual DNA

Pharmacodynamics: the target effects of a drug; what a drug does to the body

Pharmacogenetics: the study of how different drugs interact with the body in different ways based on genetic variation

Pharmacokinetics: how a drug is metabolized; what the body does to a drug

Pharmacology: the study of drugs and their origins, as well as how they interact with the body of a living organism

PharmGKB: Pharmacogenomics Knowledge Base is an interactive tool for researchers to investigate how genetic variation affects drug response, both with regards to pharmacodynamics and pharmacokinetics

Phenotype: the physical makeup, or appearance, of an organism or individual trait

Physical Trait: any trait that concerns our material makeup

Polygenic Trait: a trait that is the result of multiple gene interactions with very little environmental impact

Population: a group of individuals of one species that live in a particularly defined area

Promoter: a region of DNA at which transcription of a particular gene is initiated

Protein: a large chain or combination of multiple chains of amino acids


Qualitative Trait: a trait that is described by either its presence or absence

Quantitative Trait: a trait that varies continuously over a range of measurements and displays a normal distribution (bell curve)


Random Selection: the process by which traits become either more or less common in a population due to random chance, not because of pressures directly affecting the reproductive fitness of particular alleles; it is random because the pressures do not directly affect the fitness of particular alleles

Recessive Trait: masked by the presence of a dominant allele or trait

Recombination: a special process during meiosis that can swap pieces of your maternal and paternal chromosome copies

Relative Risk: an individual's risk based on family or genetic background compared to the general population

Repressor: transcription factors that bind to a silencer and inhibit transcriptional activity

Ribosome: a molecular machine that translates, or reads, the genetic code within the mRNA sequence and synthesizes a corresponding chain of amino acids

RNA and mRNA: ribonucleic acid; A type of nucleic acid, usually single-stranded, consisting of nucleotides with the nitrogenous bases of A, C, G, and U

RSID: reference SNV identification


Sex Chromosome: a nuclear chromosome that distinguishes the sexes: XY - male, XX - female, and can affect sex-specific traits

Silencer: a DNA sequence capable of binding transcription regulation factors, called repressors, and inhibit transcriptional activity

Silent/Synonymous Mutation: a mutation that does not change the amino acid sequence

Single Nucleotide Variation (SNV): single base change in DNA; SNVs (also known as single nucleotide polymorphisms, or SNPs) are one of the smallest kinds of mutations and are responsible for a large number of differences among humans

SNV Genotyping: determining the base at any given position in a genome, not through total genome sequencing

Somatic Cell: any cell of the body that is not a germ cell (not directly responsible for carrying the information passed on to the next generation)

Sperm: male reproductive cell

Splicing: the process of removing introns and combining exons in a mRNA sequence after transcription


TATA-box: the TATAAA sequence that can be found in the promoter of many genes and is essential to initiate transcription

Thymine (T): a type of nitrogenous base that is typically used in DNA (T basepairs with A)

Toxicity: the degree to which a drug causes negative effects

Trait: any distinguishing feature of an individual

Transcription: the step of gene expression in which a particular segment of DNA is copied into RNA

Transcription Factor: any protein that joins the transcription process by binding to DNA or to other proteins that bind DNA to regulate transcription

Translation: the process by which ribosomes read the mRNA sequence and connect the amino acids in the order specified by the sequence

Translocation: rearrangement of a large sequence of genetic information, typically transferring from one chromosome to another through DNA breakage and resealing


Uracil (U): a type of nitrogenous base that is typically used in RNA (U basepairs with A)


Variant: version of a genetic sequence or gene for which more than one version exist

Variation: diversity among members of a population

Visible Trait: any trait that is apparent through outward observation


X Chromosome: one of two mammalian sex chromosomes that can be found in both males (XY) and females (XX)


Y Chromosome: the mammalian sex-determining chromosome that can only be found in males (XY) and is passed from father to son