Genetic techniques are used in medicine to diagnose and treat inherited human disorders. Knowledge of a family history of conditions such as cancer or various disorders may indicate a hereditary tendency to develop these afflictions. Cells from embryonic tissues reveal certain genetic abnormalities, including enzyme deficiencies, that may be present in newborn babies, thus permitting early treatment. Many countries require a blood test of newborn babies to determine the presence of an enzyme necessary to convert an amino acid, phenylalanine, into simpler products. Phenylketonuria (PKU), which results from lack of the enzyme, causes permanent brain damage if not treated soon after birth. Many different types of human genetic diseases can be detected in embryos as young as 12 weeks; the procedure involves removal and testing of a small amount of fluid from around the embryo (called amniocentesis) or of tissue from the placenta (called chorionic villus sampling).
Gene therapy is based on modification of defective genotypes by adding functional genes made through recombinant DNA technology. Bioinformatics is being used to “mine” the human genome for gene products that might be candidates for designer pharmaceutical drugs.
The-initial-proposal-of-the-structure-of-DNA-by-JamesThe initial proposal of the structure of DNA by James Watson and Francis Crick, which was …[Credits : Encyclopædia Britannica, Inc.]
Sex-linked-inheritance-of-white-eyes-in-Drosophila-fliesSex-linked inheritance of white-eyes in Drosophila flies.[Credits : Encyclopædia Britannica, Inc.]
Steps-involved-in-the-engineering-of-a-recombinant-DNA-moleculeSteps involved in the engineering of a recombinant DNA molecule.[Credits : Encyclopædia Britannica, Inc.]
Dolly-the-sheep-was-successfully-cloned-in-1996-by-fusingDolly the sheep was successfully cloned in 1996 by fusing the nucleus from a mammary-gland cell of …[Credits : Encyclopædia Britannica, Inc.]
Mendels-law-of-independent-assortment-The-example-here-shows-aMendel’s law of independent assortment[Credits : Encyclopædia Britannica, Inc.]
Mendels-law-of-segregation-Cross-of-a-purple-flowered-andMendel’s law of segregation[Credits : Encyclopædia Britannica, Inc.]
Punnett-square-diagrams-are-used-to-predict-all-the-possiblePunnett square diagrams are used to predict all the possible gene combinations that could result …[Credits : Encyclopædia Britannica, Inc.]
James Watson and Francis Crick revolutionized the study of genetics when they discovered the …[Credits : Acquired from Vast Video]
Specific segments of DNA are amplified (copied) in a laboratory using polymerase chain reaction …[Credits : Encyclopædia Britannica, Inc.]
Studying bacteria has lead to the relatively new science of genetic engineering.[Credits : Acquired from Vast Video]
Advantages of budding and grafting.[Credits : Acquired from Vast Video]
Mendel’s discovery of the fundamental laws governing the science of genetics.[Credits : Acquired from Vast Video]
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