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Advances In Genetics. Selective Breeding. Selective breeding is the process of selecting organisms with desired traits to be parents of the next generation. Selective Breeding. Corn was developed this way thousands of years ago. Save the best seeds and plant the next year to get the best corn
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Selective Breeding • Selective breeding is the process of selecting organisms with desired traits to be parents of the next generation
Selective Breeding • Corn was developed this way thousands of years ago. • Save the best seeds and plant the next year to get the best corn • Over time this process produced the best corn
Inbreeding • Inbreeding involves crossing two individuals that have similar characteristics. • Inbred organism have alleles that are very similar to the parents
Inbreeding • Inbreed turkeys that are plump and grow quickly so you get fast growing and plump offspring
Inbreeding • Inbred organisms are genetically very similar • Inbreeding increases the probability that organisms may inherit alleles that lead to genetic disorders.
Inbreeding • Hip problems are common in many breeds of dogs because of inbreeding
Hybridization • Hybridization is when breeders cross two genetically different individuals to get the best traits from both parents.
Hybridization • Farmers cross corn that produces many kernels with corn that is disease resistant to create a corn that is resistant to disease and produces many kernels.
Cloning • A clone is an organism that has exactly the same genes as the organism from which was produced.
Cloning Plants • To clone plants, cut a stem from one plant and put it into water. Soon it will grow roots and develop into a new, but genetically identical plant
Cloning Animals • To clone animals you take the nucleus from the parents cell and inject it into a embryo whose nucleus has also been removed
Cloning Animals Cont. • Then you give the embryo a small electric shock to fuse the nucleus to the cell. If it works the embryo will start to develop
Cloning Animals Cont. • The embryo is then inserted into a surrogate mother where it will develop
Cloning Animals-Dolly • was cloned in 1996 • She was the first cloned mammal
Genetic Engineering • In genetic engineering, genes from one organism are transferred into the DNA of another organism
Genetic Engineering in Bacteria • Scientists genetically engineer bacteria to produce a protein called insulin • People with diabetes take insulin to help their blood absorb glucose
Genetic Engineering in Other Organisms • Scientists can insert genes into animals and plants. • Insert human genes into the cells of the cow. The cow then produces the human protein that is used to help people with hemophilia
Genetic Engineering in Other Organisms • Scientists insert genes into the cells of plants. • It can help make plants more resistant to cold temperatures or poor soil.
Gene Therapy • Gene therapy is when scientists insert copies of genes directly into a person’s cells. • Could someday be used to treat some genetic disorders
Gene Therapy Today • Gene therapy has not yet been approved by the FDA • It is still in its experimental stages • Little success since trials began in 1990
Concerns about Genetic Engineering • What are the long-terms effects of genetic engineering? • Are genetic engineered crops safe? • Is it human to genetically engineer animals? • Is it safe for the environment?
Human Genome Project • Genome is all the DNA in one cell of an organism • The main goal of the Human Genome Project has been to identify the DNA sequence of every gene in the human genome
Human Genome Project • Scientists have completed the first draft of the human genome. • there are at least 30,000 genes • The average gene has about 3,000 bases • Chromosome 1 has 2968 genes and the Y chromosome has 231 genes
DNA Fingerprinting • Today we can identify people and show whether people are related • Break down DNA from a person’s cell • Selected pieces of the DNA are used to produce a DNA fingerprint
DNA Fingerprinting • Everyone has different DNA, except for identical twins • Used to solve crimes • Identify skeletal remains • Soldiers give DNA samples
Limitations to DNA Fingerprinting • DNA is fragile • Can be difficult to read if the DNA samples are old • Inaccurate results can occur if there is a mix-up • DNA fingerprinting is expensive and time consuming.