Download Advances in genetics

Advances in genetics
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Coulter
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Selective breeding, cloning, and genetic
engineering are three methods for developing
organisms with desirable traits.
Selective breeding
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The process of selecting organisms with
desired traits to be parents of the next
generation.
Thousands of years ago what we call corn was
developed this way.
Yearly farmers saved seeds from healthy plants,
then in the spring they would plant them.
Selective breeding
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Inbreeding involves crossing two individuals
that have similar characteristics.
Two turkeys both plump and grow quickly.
Their offspring will probably have these traits.
Inbred have very similar alleles that are very
similar to those of their parents.
Genetically similar, increases the probability
that organisms may inherit genetic disorders.
inbreeding
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Hybridization, breeders cross two genetically
different individuals.
Hybrid organisms that results is bred to have
the best traits from both parents.
May cross a cord that produces many kernels
with corn that is resistant to disease.
Hybridization
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Is an organism that has exactly the same genes
as the organism from which it was produced.
It isn’t hard to clone some plants. The African
violet, just cut the stem from one plant, and put
the stem in soil.
Researchers have cloned pigs and sheep. This
method is complex. Involves taking the nucleus
of an animal’s body cell and using that to
produce a new-animal.
Cloning
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Genes from one organism are transferred into
the DNA of another organism.
Genetic engineering
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One type of genetically
engineered bacteria
produces a protein
called insulin.
Bacteria have a single
DNA molecule in the
cytoplasm.
Some bacteria cells
contain small circular
pieces of DNA called
plasmids.
Genetic engineering in
bacteria
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Scientists can also use genetic engineering
techniques to insert genes into animals.
Scientists have used this method to produce the
blood clotting protein needed by people with
hemophilia.
They have used this method in plants to enable
them to survive in cold, poor soil, and resist
insect pests.
Genetic engineering in
other organisms
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Gene therapy will involve inserting copies of a
gene directly into a person’s cells.
Doctors may be able to treat hemophilia by
correcting the allele on the X chromosome.
Gene therapy
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Some think that genetically engineered crops
may not be entirely safe.
People fear these crops may harm the
environment or cause health problems in
humans.
Scientists try to learn more about the effects of
genetic engineering.
Concerns about genetic
engineering
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The human genome project: scientists are
trying to crack a 6 billion letter long code.
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.
Scientists have learned DNA has 30,000 genes.
Someday we will know the DNA sequence of
every human gene.
Learning about human
genetics
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DNA technology used in the Human Genome
Project can also identify people and show
whether people are related.
DNA is broken into fragments, the pattern
produced is called DNA fingerprint.
Except for identical twins, no two people have
exactly the same DNA fingerprint.
DNA fingerprint