Frameshift mutationA frameshift mutation (also called a framing error or a reading frame shift) is a genetic mutation caused by indels (insertions or deletions) of a number of nucleotides in a DNA sequence that is not divisible by three. Due to the triplet nature of gene expression by codons, the insertion or deletion can change the reading frame (the grouping of the codons), resulting in a completely different translation from the original.
MutationAlteration in the nucleotide sequence of a genomeThree major single-chromosome mutations: deletion (1), duplication (2) and inversion (3).In biology, a mutation is an alteration in the nucleic acid sequence of the genome of an organism, virus, or extrachromosomal DNA. Mutations result from errors during replication, mitosis, meiosis, or damage to DNA, which then may trigger error-prone repair or cause an error during replication (translesion synthesis).
DNA replicationDNA replication is the process by which a cell makes exact copies of its DNA. This process occurs in all organisms and is essential to biological inheritance, cell division, and repair of damaged tissues. DNA replication ensures that each of the newly divided daughter cells receives its own copy of each DNA molecule. DNA most commonly occurs in double-stranded form, made up of two complementarystrands held together by base pairing of the nucleotides comprising each strand.
Missense mutationIn genetics, a missense mutation is a point mutation in which a single nucleotide change results in a codon that codes for a different amino acid. It is a type of nonsynonymous substitution. Missense mutations change amino acids, which in turn alter proteins and may alter a protein's function or structure. These mutations may arise spontaneously from mutagens like UV radiation, tobacco smoke, an error in DNA replication, and other factors.
Transition (genetics)Transition, in genetics and molecular biology, refers to a point mutation that changes a purinenucleotide to another purine (A ↔ G) or a pyrimidine nucleotide to another pyrimidine (C ↔ T). Transitions are common in genomes; approximately two out of three single nucleotide polymorphisms (SNPs) are transitions. Molecular basisTransitions can be caused by several mechanisms, including spontaneous deamination and tautomerization.
NucleotideNucleotides are organic molecules composed of a nitrogenous base, a pentose sugar and a phosphate. They serve as monomeric units of the nucleic acidpolymers – deoxyribonucleic acid (DNA) and ribonucleic acid (RNA), both of which are essential biomolecules within all life-forms on Earth. Nucleotides are obtained in the diet and are also synthesized from common nutrients by the liver.Nonsense mutationIn genetics, a nonsense mutation is a point mutation in a sequence of DNA that results in a nonsense codon, or a premature stop codon in the transcribed mRNA, and leads to a truncated, incomplete, and possibly nonfunctional protein product. Nonsense mutations are not always harmful; the functional effect of a nonsense mutation depends on many aspects, such as the location of the stop codon within the coding DNA.
DNADeoxyribonucleic acid (pronunciation; DNA) is a polymer composed of two polynucleotide chains that coil around each other to form a double helix. The polymer carries genetic instructions for the development, functioning, growth and reproduction of all known organisms and many viruses. DNA and ribonucleic acid (RNA) are nucleic acids.
PurinePurine is a heterocyclic aromatic organic compound that consists of two rings (pyrimidine and imidazole) fused together. It is water-soluble. Purine also gives its name to the wider class of molecules, purines, which include substituted purines and their tautomers. They are the most widely occurring nitrogen-containing heterocycles in nature. In nucleic acids, two types of nucleobases are purine derivatives: adenine (A) and guanine (G).
Synonymous substitutionA synonymous substitution (often called a silent substitution though they are not always silent) is the evolutionary substitution of one base for another in an exon of a gene coding for a protein, such that the produced amino acid sequence is not modified.
PyrimidineNames Preferred IUPAC namePyrimidineSystematic IUPAC name1,3-DiazabenzeneOther names 1,3-Diazinem-DiazineIdentifiers CAS Number289-95-23D model (JSmol)Interactive imageBeilstein Reference103894 ChEBICHEBI:16898ChEMBLChEMBL15562ChemSpider8903ECHA InfoCard100.005.479EC Number206-026-0Gmelin Reference49324 KEGGC00396MeSHpyrimidinePubChemCID9260UNIIK8CXK5Q32LCompTox Dashboard(EPA)DTXSID1051228InChIInChI=1S/C4H4N2/c1-2-5-4-6-3-1/h1-4HKey: CZPWVGJYEJSRLH-UHFFFAOYSA-NInChI=1/C4H4N2/c1-2-5-4-6-3-1/h1-4HKey: CZPWVGJYEJSRLH-UHFFFAOYATSMILESn1cnccc1Properties Chemical formulaC4H4N2Molar mass80.088 g mol Density1.016 g cm Melting point20 to 22 °C (68 to 72 °F; 293 to 295 K) Boiling point123 to 124 °C (253 to 255 °F; 396 to 397 K) Solubility in waterMiscible (25°C) Acidity (pKa) 1.10 (protonated pyrimidine) Hazards GHS labelling:[1]PictogramsSignal wordDangerHazard statementsH226, H318Precautionary statementsP210, P233, P240, P241, P242, P243, P264+P265, P280, P303+P361+P353, P305+P354+P338, P317, P370+P378, P403+P235, P501Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).Yverify ( ?)
RNAFamily of large biological moleculesA hairpin loop from a pre-mRNA. Highlighted are the nucleobases (green) and the ribose-phosphate backbone (blue). This is a single strand of RNA that folds back upon itself. Ribonucleic acid (RNA) is a polymeric molecule that is essential for most biological functions, either by performing the function itself (non-coding RNA) or by forming a template for the production of proteins (messenger RNA).
GeneticsGenetics is the study of genes, genetic variation, and heredity in organisms. It is an important branch in biology because heredity is vital to organisms' evolution. Gregor Mendel, a Moravian Augustinian friar working in the 19th century in Brno, was the first to study genetics scientifically. Mendel studied "trait inheritance", patterns in the way traits are handed down from parents to offspring over time.*As an Amazon Associate I earn from qualifying purchases.