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The Doll

Decent Essays

Part I: The Doll
They never found her body, but they did find the doll.
Its porcelain head peeked out from the soil in the forest. Its right eye was missing and a few worms had burrowed into the vacant socket and made a quaint home inside. They thought that it might be the corpse at first, but soon realized it was only a doll. They dug it up and sent it away to be examined.
As I understood it back then: the doll possessed deoxyribonucleic acid, or DNA, that could be analyzed to match possible suspects whose DNA matched that found at the crime scene. Almost every cell in our body contains DNA. It is a hereditary material located in the nucleus. “The information in DNA is stored as a code made up of four chemical bases: adenine (A), guanine …show more content…

Most DNA is found inside the nucleus of a cell, where it forms the chromosomes. Chromosomes have proteins called histones that bind to DNA. DNA has two strands that twist into the shape of a spiral ladder called a helix. DNA is made up of four building blocks called nucleotides: adenine (A), thymine (T), guanine (G), and cytosine (C). The nucleotides attach to each other (A with T, and G with C) to form chemical bonds called base pairs, which connect the two DNA strands. Genes are short pieces of DNA that carry specific genetic information. …show more content…

This technique simultaneously detects lots of minisatellites in the genome to produce a pattern unique to an individual, or a DNA fingerprint.
Sir Alec Jefferys discovered DNA fingerprinting in 1984 after he realized that variations in human DNA could be detected in the form of short sequences of repetitive DNA (4). On average, 99.9% of human DNA is the same from person to person however; the 1% remaining is what makes each person unique. Although this seems like a small amount, there are approximately 3 million base pairs in these short, repetitive sequences that distinguish one person from another. DNA fingerprinting could be carried out using two possible methods: polymerase chain reaction, or PCR, and restriction fragment length polymorphism, or RFLP. To begin either method, DNA must be isolated from blood, semen, vaginal fluids, hair roots, skin, skeletal remains, or objects. In the process of PCR, small samples of DNA could be used because PCR utilizes DNA’s unique ability to make many copies of itself.
Like DNA replication within an organism, PCR requires a DNA polymerase enzyme that makes new strands of DNA, using existing strands as templates. The DNA polymerase typically used in PCR is called Taq polymerase, after the

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