What is a genome? A genome is the full set of genetic information that an organism carries in its DNA. The study of any genome starts with the analysis of chromosomes. Chromosomes are bundles of DNA and protein found in the nuclei of eukaryotic cells. Fruit fly chromosomes

How are chromosomes analyzed? To study chromosomes, scientists photograph chromosomes in mitosis and arrange them in a picture known as a karyotype. A karyotype shows the complete diploid set of chromosomes grouped together in pairs, arranged in order of decreasing size. A typical human karyotype contains 46 chromosomes arranged in 23 pairs. 1. Define What is a karyotype?

COMPONENTS of a Human Karyotype Homologous chromosomes Pairs from MOM/DAD 2. Autosomes (22pairs) 3. Sex chromosomes (23rd pair)

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Down’s Syndrome Called TRISOMY 21 genetic disorder that occurs in approximately 1 of 800 live births SYMPTOMS Cognitive impairment Learning disabilities Develpmental delays Low muscle tone (infancy) Characteristic facial features Heart defects Other health issues CAUSES Non-disjunction of the 21st chromosome

NONDISJUNCTION

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Klinefelter’s Syndrome Klinefelter’s syndrome occurs in about 1 out of 1,000 males. XXY (extra copy of an X chromosome) SYMPTOMS Not always noticiable symptoms Large hips Small breasts Fat around the abdomen Small testicles CAUSES Non-disjunction of the sex chromosomes in either sperm or egg

DNA FINGERPRINTING

How is DNA fingerprinting used to study genomes? No two individuals, except identical twins, are genetically identical. DNA fingerprinting analyzes sections of DNA that may have little or no function but that vary widely from one individual to another. . (contd.)

HOW IS DNA Fingerprinted? DNA is cut by restriction enzymes scientists use gel electrophoresis to separate and analyze the differently sized fragments. Scientists compare the BANDS made 2. Describe How do scientists separate DNA?

DNA fingerprinting is used to study genomes?

Teachers…Click on the following link http://www.rocklin.k12.ca.us/staff/avrudny/Science/Advanced_Biology/Unit_8/DNA_Fingerprinting_Activity.pdf Focus on the bottom of the activity only! Crime Scene Analysis CASE 1 and CASE 2

What have we learned about the human genome? The Human Genome Project was an international effort to sequence all 3 billion base pairs of human DNA. 2.Other important goals included to support research so that we can cure human diseases 3. Explain What are some of the goals of the Human Genome Project?

How do humans genetically modify organisms? Human beings have always tried to improve the plants and animals they use for food, work, and companionship. Selective breeding –crossing two individuals with desired traits (choosing what you want) Why?—to get desired traits in offspring

Two Methods of Selective Breeding 1.Hybridization 2.Inbreeding Crossing dissimilar individuals together to bring together the best of both organisms Continued breeding of individuals with similar characteristics

What are transgenic organisms? It is possible to construct organisms that are transgenic, containing genes from other species. Genetic engineers can now produce transgenic plants, animals, and microorganisms. By examining the traits of a genetically modified organism, it is possible to learn about the function of the transferred gene. This ability has contributed greatly to our understanding of gene regulation and expression.

What is recombinant DNA? Recombinant DNA consists of DNA molecules that have been taken from two sources and then recombined. Recombinant-DNA technology makes it possible to construct DNA molecules with nearly any combination of genes.

Cloning Clone – member of a population of genetically identical cells First dog successfully cloned Clone – member of a population of genetically identical cells

Infer Using the example of the sheep cloning, why wouldn’t the cloned lamb resemble its foster mother?

Gene Therapy Gene therapy is a relatively recent, and still highly experimental, approach to treating human disease Identify the faulty gene Inactivating, or “knocking out,” a mutated gene that is functioning improperly. Introducing a new gene into the body to help fight a disease.