Advances in Genetics - ScienceRocks8

deadstructureBiotechnology

Dec 14, 2012 (4 years and 11 months ago)

209 views

ADVANCES IN GENETICS

Key Concepts


What are three ways of
producing organisms with
desired traits?


What is the goal of the Human
Genome Project?

KEY TERMS


Selective breeding


Inbreeding


Hybridization


Clone


Genetic engineering


Gene therapy


genome

SELECTIVE BREEDING


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

INBREEDING


Crossing 2 individuals that have


similar characteristics


Ex. Crossing 2 turkeys that are


both plump and grow quickly
-

offspring are likely
to 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

HYBRIDIZATION


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

CLONING


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

GENETIC ENGINEERING


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


Used to produce medicines and improve food
crops

GENETIC ENGINEERING IN BACTERIA


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

GENETIC ENGINEERING IN OTHER ORGANISMS


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

GENE THERAPY


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

GENE THERAPY

HURDLES FOR GENE THERAPY


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
g
enetically 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


CONCERNS ABOUT GENETIC ENGINEERING


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


LEARNING ABOUT HUMAN GENETICS


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 FINGERPRINTING


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

SOURCES


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