Key Concepts•What are three ways of producing organisms with desired traits?•What is the goal of the Human Genome Project?

Selective breeding Inbreeding Hybridization Clone Genetic engineering Gene therapy genome

One of 3 methods used to develop organisms with desirable traits

Select organisms with desirable traits to be parents of next generation

Ex: Corn, dogs Two selective breeding

techniques are inbreeding and hybridization

Crossing 2 individuals that have similar characteristics Ex. Crossing 2 turkeys that are both plump and grow quickly- offspring

are likely to have both those desirable qualities

Inbred organisms have alleles that are very similar to parents

Inbred organisms are genetically very similar so they may inherit alleles that lead to genetic disorders

Breeders cross 2 genetically different individuals

Hybrid that results is bred to have best traits from both parents

Ex. Crossing one type of corn with large kernels with another that is resistant to disease. Result might be hybrid corn with both of the desired traits

Clone – an organism that has exactly the same genes as the organism from which it was produced

Easy to clone many plants – cut a stem, put it in soil and water, and it will develop into a new plant – genetically the same as the parent

Researchers have been cloning animals such as sheep, cows, goats and pigs

Click and Clone

Genes from one organism are transferred into the DNA of another organism

Used to produce medicines and improve food crops

Used to produce insulin Bacteria has 1 DNA molecule in the cytoplasm Also has small circular pieces of DNA called

plasmids Scientists insert a human gene into the plasmid The bacteria and all its offspring will now make

the protein that this gene codes for –in this case insulin

Since bacteria reproduce very quickly, large amounts of insulin can be produced

Can use technique to insert genes into other animals

Human genes can be inserted into the cells of cows – The cows will produce the protein for which the gene codes in their milk

This has been used to produce the blood clotting protein needed by people with hemophilia

Genes have also been inserted into plants to help them survive in cold temperatures and resist insect pests

Using genetic engineering to correct genetic disorders

Involves inserting copies of a gene directly into a person’s cells

Ex. To treat hemophilia, doctors would replace the defective allele on the X chromosome so the person’s blood would clot normally

First, scientists must find the best way to correct the genetic defect that is causing the disorder Correct or increase the defective cell product Make diseased cells weaker Block operation of diseased cells

Second – scientists must find a way to carry the genetically engineered DNA to target cells Viruses are an excellent candidate to deliver the

genes because they infect living cells Virus must be genetically engineered to render it

harmless

Some people are concerned about long-term effects of genetic engineering

Ex. Are genetically modified foods safe? Concerns that they may harm the environment or

cause health problems in humans

Scientists are trying to address these concerns and learn more about the effects of genetic engineering

The Human Genome Project

Genome – all the DNA in one cell of an organism

Main goal of Human Genome Project has been to identify the DNA sequence of every gene in the human genome

Completed first draft - found that we have at least 30,000 genes. Average gene has 3,000 bases

DNA technology can be used to identify people and show relationships DNA is broken down into small

fragments. Selected fragments are used to produce a pattern similar to a fingerprint

Except for identical twins no 2 people have the same DNA fingerprint

http://www.energy-dimension.com/12-bizarre-examples-of-genetic-engineering/