application of reproduction and genetics

• Anopheles gambiae


  The vector of malaria, otherwise known as the mosquito. It has rapidly evolved resistance to many insecticides.
• Clones


  The genetically identical offspring produced as a result of cloning
• Cloning


  A method of producing genetically identical offspring by asexual reproduction
• Complementary DNA (cDNA)


  A single strand of DNA complementary to the mRNA template strand which is usually synthesised during reverse transcription
• Cystic fibrosis


  A genetic disorder characterised by the production of thick, sticky mucus that causes lung infections and scarring
• DNA ladder


  A set of DNA fragments of known size (standards) used to estimate the fragment lengths of a molecule run on a gel during electrophoresis
• DNA ligase


  An enzyme that joins the sugar-phosphate backbone of two DNA segments
• DNA polymerase


  An enzyme that synthesises a double-stranded molecule of DNA from a single template strand using complementary nucleotides
• Drisapersen


  An experimental drug which aims to treat DMD by exon skipping. It introduces a 'molecular patch' over the mutated exon, enabling the gene to be read. A shorter, more functional type of dystrophin is synthesised.
• Duchenne muscular dystrophy (DMD)


  An X-linked recessive condition that is characterised by muscle degeneration and weakness. It is caused by one or more mutations in the dystrophin gene that prevent the production of dystrophin.
• Exon


  A region of DNA that codes for an amino acid sequence
• Functional mRNA


  The final mRNA product that has had introns removed, as well as having undergone other post-transcriptional changes
• Gel electrophoresis


  A technique that separates nucleic acid fragments or proteins by size using electric current
• Gene therapy


  A therapeutic technique in which a faulty allele is replaced with a functional allele in order to treat or prevent disease
• Genetically modified (GM) organism


  An organism that has had its genome altered
• Genetic counselling


  A service that provides information and advice to people affected by or at risk of genetic diseases. This helps individuals and families to make informed decisions.
• Genetic engineering


  The modification of the genome of an organism by the insertion of a desired gene from another organism. This enables the formation of organisms with beneficial characteristics.
• Genetic fingerprinting


  A technique used to genetically identify an organism. It has applications in forensics.
• Genetic screening


  Testing individuals for certain faulty alleles. This can be used to detect disorders such as cystic fibrosis, Huntington's disease and thalassemia.
• Genomics


  A field of biology that focuses on the evolution, structure, function and mapping of genomes.
• Germ line therapy


  A type of gene therapy in which a faulty allele is replaced with a functional allele in germ cells or a very early embryo. The effects of this are permanent and can be inherited.
• Human Genome Project


  An international research project involving thousands of scientists which used Sanger sequencing to successfully map the entire human genome.
• Huntington's disease


  A genetic disorder characterised by the progressive degeneration of nerve cells in the brain, reducing the affected individual's ability to think, talk and move.
• Intron


  A non-coding sequence of DNA
• Malaria


  A disease caused by the protoctista Plasmodium that lives within two hosts, mosquitoes (Anopheles gambiae) and humans. It causes recurrent episodes of fever and can be fatal.
• Marker gene


  An additional gene inserted into a plasmid that is used to aid in the identification of host cells that have taken up the desired gene. Marker genes are easily recognisable e.g. provide antibiotic resistance.
• Next-generation sequencing (NGS)


  The method of DNA sequencing used in the 100K Genome Project. It is faster, cheaper and more accessible than Sanger sequencing.
• Personalised medicine


  A form of medical care that enables doctors to provide healthcare customised to an individual's genotype.
• Plasmodium sp.


  The parasite that causes malaria. It has developed multi-drug resistance.
• Polymerase Chain Reaction (PCR)


  An in vitro technique used to rapidly amplify fragments of DNA.
• Post-transcriptional processing


  A set of biological processes, including the removal of introns, that modify pre-mRNA to produce functional mRNA following transcription.
• Pre-mRNA


  The product of transcription before any post-transcriptional regulation.
• Primers


  Short nucleotide sequences, complementary to one end of each of the DNA fragments.
• Recognition sequences


  Specific base sequences of DNA that restriction enzymes cut.
• Recombinant DNA


  A combination of DNA from two different organisms.
• Recombinant DNA technology


  The process by which segments of DNA are transferred from one organism to another.
• Restriction endonucleases


  Enzymes that cut DNA molecules at recognition sequences creating sticky ends.
• Reverse transcriptase


  An enzyme that synthesises DNA from RNA.
• Sanger sequencing


  The method of DNA sequencing used in the Human Genome Project that involves the formation of DNA fragments of varying lengths. This process takes a long time.
• Short tandem repeats (STRs)


  Sections of repeated nucleotides within introns that produce variation in individuals.