14-3 Human Molecular Genetics Photo credit: Richard Hutchings/Photo Researchers, Inc. Copyright Pearson Prentice Hall
Copyright Pearson Prentice Hall Human DNA Analysis Human DNA Analysis There are roughly 6 billion base pairs in your DNA. Biologists search the human genome using sequences of DNA bases. Copyright Pearson Prentice Hall
Copyright Pearson Prentice Hall Human DNA Analysis Genetic tests are available for hundreds of disorders. DNA testing can pinpoint the exact genetic basis of a disorder. Copyright Pearson Prentice Hall
Copyright Pearson Prentice Hall Human DNA Analysis DNA Fingerprinting DNA fingerprinting analyzes sections of DNA that have little or no known function but vary widely from one individual to another. Only identical twins are genetically identical. DNA samples can be obtained from blood, sperm, and hair strands with tissue at the base. Copyright Pearson Prentice Hall
A DNA fingerprint is a type of restriction map. DNA fingerprints are based on parts of an individual’s DNA that can by used for identification. noncoding regions of DNA Number of nucleotide repeats a person’s molecular identity banding pattern on a gel is a DNA fingerprint
DNA fingerprinting is used for identification. DNA fingerprinting and probability of a match. Many people have the same number of repeats in a certain region of DNA. The probability that two people share identical numbers of repeats in several locations is very small. (mother) (child 1) (child 2) (father)
Copyright Pearson Prentice Hall Human DNA Analysis Remember- Chromosomes contain large amounts of DNA called repeats that do not code for proteins. This DNA pattern varies from person to person. Copyright Pearson Prentice Hall
Copyright Pearson Prentice Hall Human DNA Analysis Restriction enzymes are used to cut the DNA into fragments containing genes and repeats. Copyright Pearson Prentice Hall
Copyright Pearson Prentice Hall Human DNA Analysis DNA fragments are separated using gel electrophoresis. Fragments containing repeats are labeled. This produces a series of bands—the DNA fingerprint. Copyright Pearson Prentice Hall
Individual probabilities are multiplied to find the overall probability of two DNA fingerprints randomly matching. 1/500 x 1/90 x 1/ 120 = 1/5,400,000 or 1 chance in 5.4 million people Several regions of DNA are used to make DNA fingerprints.
Copyright Pearson Prentice Hall Human DNA Analysis DNA fingerprinting is used in several ways. evidence in criminal cases paternity tests immigration requests studying biodiversity Tracking genetically modified crops Photo credit: ©Leonard Lessin/Peter Arnold, Inc Copyright Pearson Prentice Hall 11
Genomics and Bioinformatics Genomics is the study of genomes. can include the sequencing of the genome comparisons of genomes within and across species Photo credit: ©Leonard Lessin/Peter Arnold, Inc Copyright Pearson Prentice Hall 12
Genomics and Bioinformatics Gene sequencing is determining the order of DNA nucleotides in genes or in genomes. The genomes of several different organisms have been sequenced. Photo credit: ©Leonard Lessin/Peter Arnold, Inc Copyright Pearson Prentice Hall 13
The Human Genome Project What is the goal of the Human Genome Project? Copyright Pearson Prentice Hall
The Human Genome Project The Human Genome Project is an ongoing effort to analyze the human DNA sequence. In 1990, scientists in the United States and other countries began the Human Genome Project. In June 2000, a working copy of the human genome was essentially complete. It has sequenced all of the DNA base pairs and chromosomes. Copyright Pearson Prentice Hall
The Human Genome Project Research groups are analyzing the DNA sequence, looking for genes that may provide clues to the basic properties of life. Biotechnology companies are looking for information that may help develop new drugs and treatments for diseases. Copyright Pearson Prentice Hall
The Human Genome Project Bioinformatics is the use of computer databases to organize and analyze biological data. DNA microarrays allows scientists to study the expression of many genes at once. It is used to compare gene expression in different types of cells. Proteomics is the study and comparison of proteins. It is used to study evolutionary relationships and human disease. Copyright Pearson Prentice Hall 17
Copyright Pearson Prentice Hall 14–3 Copyright Pearson Prentice Hall
Copyright Pearson Prentice Hall 14–3 DNA fingerprinting analyzes sections of DNA that have little or no known function but are identical from one individual to another. little or no known function but vary widely from one individual to another. a function and are identical from one individual to another. a function and are highly variable from one individual to another. Copyright Pearson Prentice Hall
Copyright Pearson Prentice Hall 14–3 DNA fingerprinting uses the technique of gene therapy. allele analysis. gel electrophoresis. gene recombination. Copyright Pearson Prentice Hall
Copyright Pearson Prentice Hall 14–3 Repeats are areas of DNA that do not code for proteins. code for proteins. are identical from person to person. cause genetic disorders. Copyright Pearson Prentice Hall
Copyright Pearson Prentice Hall 14–3 Data from the human genome project is available only to those who have sequenced the DNA. to scientists who are able to understand the data. by permission to anyone who wishes to do research. to anyone with Internet access. Copyright Pearson Prentice Hall
Copyright Pearson Prentice Hall 14–3 Which statement most accurately describes gene therapy? It repairs the defective gene in all cells of the body. It destroys the defective gene in cells where it exists. It replaces absent or defective genes with a normal gene. It promotes DNA repair through the use of enzymes. Copyright Pearson Prentice Hall
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