dna

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DNA

n. scientifically, deoxyribonucleic acid, a chromonal double chain (the famous "double helix") in the nucleus of each living cell the combination of which determines each individual's hereditary characteristics. In law, the importance is the discovery that each person's DNA is different and is found in each living cell, so a hair, blood, skin or any part of the body can be used to identify and distinguish an individual from all other people. DNA testing can result in proof of one's involvement or lack of involvement in a crime scene. While recent DNA tests have proved a convicted killer on death row did not commit a crime and resulted in his release, current debate concerns whether DNA evidence is scientifically certain enough to be admitted in trials. The trend is strongly in favor of admission.

dna

noun authentication, certification, confirmation of identity, proof of identity, scientific evidence, scientific means of designation, scientific means of identity, scientific means to distinguish a person, scientific method to reveal identity, substantiation, validation of identity, verification of identity, deoxyribonucleic acid
Associated concepts: appeal of a case, DNA fingerprint, DNA polymerase, forensics, overturning a case, reversal of a case

DNA

abbreviation for deoxyribonucleic acid, a chemical which is found in virtually every cell in the body and which carries genetic information. Except for identical twins, each person's DNA is unique. DNA profiling doesn't allow the examination of every single difference between people's DNA so the concentration will be on those aspects which are most likely to yield a difference. DNA can be extracted from any cells that contain a structure called the nucleus, for example, blood, semen, saliva or hair.

Mitochondrial DNA is inherited only from a person's mother. Brothers and sisters have the same mitochondrial DNA type as their mother. This feature of mitochondrial DNA can be used for body identification. The γ-chromosome is present only in men and is largely unchanged as it passes through the male line of a family. The usefulness of the technique in criminal matters is vastly enhanced by the extent to which it is possible to compare a sample with other individuals. To this end there is a National DNA Database maintained by the ASSOCIATION OF CHIEF POLICE OFFICERS and managed by the FORENSIC SCIENCE SERVICE. Techniques vary. There is a UK offence of DNA theft. It is also of assistance in paternity matters.

References in periodicals archive ?
Visions sketches what might emerge from three 20th-century scientific upheavals: the "computer revolution," the "biomolecular revolution," and the "quantum revolution." These revolutions are interconnected, as Kaku notes; discovery of the DNA double helix, for example, relied on X-ray crystallography, a technique derived from quantum physics.
What is emerging from this effort is a conception of the mind so foreign to common notions, so at odds with the view of the average person, that this idea has been called "the astonishing hypothesis" by Nobel laureate Francis Grick, co-discoverer of the DNA double helix. Research and theory from such fields as neuroscience, philosphy, cognitive psychology, modern physics, computer science are converging to provide a bold new picture picture of the mind as a physical component of the natural world, subject to scientific laws, accessible to experimentation, and therefore open to understanding, prediction, and control.
Even so, the 170,000-[ft.sup.2], $61 million building comes across as the kind of place you'd want to work in - lots of sunlight, a cappuccino bar and other spaces that encourage staff interaction, prominent views of the bay and Mount San Bruno, and thoughtful natural landscaping - as Lab of the Year judge Jerry King says, a building "well integrated with its south San Francisco Bay site." There's even a playful rendition in grass of a DNA double helix on the berm between the center and the adjacent Quality Control Lab.
In cell division, each DNA double helix would separate into two strands, and each strand would build up its complementary strand on itself; an adenine fitting over every thymine on the strand, a thymine over every adenine, a guanine over every cytosine, and a cytosine over every guanine.
From a computer scientist's viewpoint, the DNA double helix is a clever and robust information storage and transmission system.
In the new study, he introduces a synthetic molecule which folds into a helical structure that mimics surface features of the DNA double helix, and whose precise shape can be altered in a modular fashion by the attachment of various substituents.
The dynamic nature of the DNA double helix that maintains the stability of the genome forms the basis of the research.
The Doodle on shows a cartoon illustration of Franklin looking at the DNA double helix, alluding to her work on the X-ray diffraction images of DNA, which in turn led to the discovery of its distinctive structure, the report added.
An interdisciplinary team from Columbia University that includes electrical engineers from Columbia's Engineering School, together with researchers from the University's departments of Physics and Chemistry show how, for the first time, transistors can be used to detect the binding of the two halves of the DNA double helix with the DNA tethered to the transistor sensor.
DNA's chemical components confer on it a powerful versatility, rooted in the forces that bind one strand of the DNA double helix to the other.
Pupils at the Dixie Grammar School are making a DNA double helix, while mythical animals are being created by youngsters at Market Bosworth High School.
Thirty years later it is an unexpected pleasure to be invited to join the chorus, indeed the symphony, celebrating the golden anniversary of the DNA double helix and the sequencing of a complete human genome and to reflect upon how deciphering the structure of DNA was fundamental to the fields of mutagenesis and genetic toxicology and more recently to the emerging field of toxicogenomics.