Genetics: Implications
Objective 1 – Pedigrees – p. 544 & 560
Pedigree – diagram that shows the genetic relationships among individuals (family tree)
• Use pedigrees for humans, since we cannot ethically ‘test’ on humans
• Can be used to determine the likelihood of passing on genetic disorders, and how it is passed on (autosomal dominant/recessive, sex link dominant/recessive)
• Ex. Hemophilia in the Royal Family (p. 560)
How Pedigrees Work
• Squares – males
• Circles – females
• Individuals with the disorder – shaded
• Individuals without – clear
• Different generations – Roman numerals or different “levels” on the pedigree
• Sometimes, carriers are shown by half-shading (not on a public though)
Figuring out a Pedigree – the shortcut
• Look for any family that have offspring with a phenotype different than both their parents – that child is recessive
• Any girls with a recessive phenotype who have a father or son with a dominant phenotype? – If she does, it cannot be X-linked. If it was X-linked, she’d give a recessive allele to her son, so he couldn’t be dominant.
http://www.youtube.com/watch?v=HbIHjsn5cHo – solving a pedigree (9:12)
http://www.youtube.com/watch?v=qolJlhVg6mw – the fast way (6:41)
Answers to 2nd side of pedigree work sheet #1
http://youtu.be/-UnA1AlN85g - video 63
http://youtu.be/Bdx82wNBSvw - video 78A sheet 1
http://youtu.be/YEMFLlVAgJw - video 78B sheet 1
Objective 1 – Pedigrees – p. 544 & 560
Pedigree – diagram that shows the genetic relationships among individuals (family tree)
• Use pedigrees for humans, since we cannot ethically ‘test’ on humans
• Can be used to determine the likelihood of passing on genetic disorders, and how it is passed on (autosomal dominant/recessive, sex link dominant/recessive)
• Ex. Hemophilia in the Royal Family (p. 560)
How Pedigrees Work
• Squares – males
• Circles – females
• Individuals with the disorder – shaded
• Individuals without – clear
• Different generations – Roman numerals or different “levels” on the pedigree
• Sometimes, carriers are shown by half-shading (not on a public though)
Figuring out a Pedigree – the shortcut
• Look for any family that have offspring with a phenotype different than both their parents – that child is recessive
• Any girls with a recessive phenotype who have a father or son with a dominant phenotype? – If she does, it cannot be X-linked. If it was X-linked, she’d give a recessive allele to her son, so he couldn’t be dominant.
http://www.youtube.com/watch?v=HbIHjsn5cHo – solving a pedigree (9:12)
http://www.youtube.com/watch?v=qolJlhVg6mw – the fast way (6:41)
Answers to 2nd side of pedigree work sheet #1
http://youtu.be/-UnA1AlN85g - video 63
http://youtu.be/Bdx82wNBSvw - video 78A sheet 1
http://youtu.be/YEMFLlVAgJw - video 78B sheet 1
Recessive Sex-linked Disorders
Hemophilia
- sex-linked disorder; blood is unable to clot because it lacks certain
protein. Recessive gene is carried on the X chromosome - mostly affects males. Severe bleeding.
Duchenne Muscular Dystrophy
- Sex linked disorder; muscle tissue breaks down during childhood due to an inactive form of protein required for normal muscle function.
Recessive gene carried on X chromosome. Few live beyond their teens.
Color -Blindness -
alleles that detect red and green colors are found on the X chromosome. If one of the pigments that help us distinguish these colors is defective, then the person cannot tell the difference between red and green.
Autosomal Recessive Genetic Disorders
• Tay-Sachs Disease
- inherited recessive disorder resulting from a lack of an enzyme that breaks down lipids in the brain. Lipids build up without this enzyme, causing brain damage; appears before the age of one, with death occurring within the first few years of life.
•Phenylketonuria (PKU)
- recessive inherited disorder; enzyme that breaks down phenylalanine is missing. Without this enzyme, phenylalanine breaks down into chemicals that are harmful to the brain. Can be diagnosed by a urine test at birth. A diet low in phenylalanine may avoid brain damage in affected individuals.
•Albinism
– recessive disorder in which the eyes, skin and hair have no pigment. A person with albinism lacks an enzyme needed to produce melanin. People with this condition must take care not to expose themselves to the sun.
Co-dominant Disorder
•Sicke-cell disease
- recessive inherited disorder; red blood cells have abnormal sickle shape causing them to clump, resulting in a lack of oxygen in the blood and pain and weakness.
•Caused by the change of one base of a 300 amino acid chain of hemoglobin: GAA (glutamic acid) to GUA (valine). Most people do not live past childhood. No cure.
•There is a heterozygous advantage in African populations that carry sickle-cellanemia: they are more resistant to malaria.
Incomplete Dominant Disorder
•Familial Hypercholesterolemia (FH) – those who are homozygous recessive have no receptors to take low-density lipoproteins into cells. Therefore their cholesterol is 6X normal, resulting in atherosclerosis and a heart attack by age two.
•Those who are heterozygous for the condition have half the normal amount of receptors,resulting in high (2X) but manageable cholesterol levels.
Heart attack by age 35.
Autosomal Dominant Disorder
•progeria – rare autosomal dominant disorder that causes rapid aging.
•Huntington’s Disease
- Every individual who has the dominant allele develops Huntington’s. Those infected are usually asymptomatic until after 35 years of age. This
disease causes a progressive breakdown of brain cells, leading to death. Symptoms include irritability, memory loss, and loss of muscle coordination.
Objective 2
Genetic Engineering – the process of producing altered DNA, usually by breaking a DNA molecule and inserting new genes.
Objective 3 - The importance of Genetic Counselling (p. 606)
Genetic Counselling – medical professional who consults with the couple to gather information about family history to construct pedigrees.
Helps determine the risk of having a child with a disorder.
•No treatment or cure is known for many inherited disorders.
•Those who may be carriers can be tested and counseled before having children •Inform them of the risks of having affected children; education to help with fears/anxiety
Objective 4 - Detecting Genetic Disorders - p. 607
•Karyotyping - a technique for examining the chromosome makeup of an individual; can detect genetic disorders in a fetus.
•Amniocentesis - a technique used to detect genetic disorders in a fetus; a long needle is used to draw out fluid from the amniotic sac in which the fetus lives; 16th week of pregnancy. Can check for presence or absence of enzymes (Tay
Sachs) or karyotyped to determine if chromosomes are abnormal, missing or extra.
•Chorionic villus sampling
- a technique used by physicians to detect genetic disorders; a sample of the chorion, a part of the placenta is removed for genetic analysis.
Can be done earlier than an amnio.
•Ultrasound high frequency sound waves are reflected off the fetus to produce an image that can be studied to determine the size and position of a developing fetus.
•Fetoscopy - a technique that allows direct observation of the fetus and surrounding tissues by inserting a viewing scope with a special light into the uterus; blood and cell samples may be taken by using tools in addition to the endoscope.
•Genetic markers- any characteristic that provides information about an organism’s genome.
–Linked marker – a known sequence of nucleotides next to a gene that causes a disorder.
–Gene-specific marker – a sequence of DNA that is a part of the gene itself.
–Seeing these sequences shows us that the gene causing a disorder is present. Using a radioactive complementary DNA strand that will attach to the ‘sequence’ in an experimental setting will show scientists that the defective gene is present.
Objective 5 - Treating Genetic Disorders
•Screening and prevention
–Detecting a genetic disorder at birth (Phenylketonuria –PKU)
–Using preventative measures (strict diets) children can grow to lead normal lives
•Surgery –Some conditions can be treated through surgery
–Cleft palate – physical development that results in a groove in the upper lip androof of the mouth. Reconstructive surgery can fix this problem
•Environmental control
–Control the environment in which a person navigates
–Ex. Albinism – lack pigment melanin (no protection against mutagenic effects of sunlight). People with albinism avoid sunlight or wear protective clothing/glasses
•Gene therapy (See pic immedicately below)
–Transferring normal or modified genes into an individual’s defective cells
–In theory, the genes transferred will allow the recipient to begin to synthesize (make) the missing polypeptide, thus reversing the symptoms of the
disorder –Ex. Case in Quebec: Abnormally high cholesterol in blood
•Had heart attack at age 16; bypass by age 26
•Both brothers had died of heart attacks in 20’s
•Patient had 15% of her liver removed
•Healthy human gene she lacked was inserted into the DNA of a harmless virus
•This virus was added to the portion of liver that was removed
•Virus ‘infected’liver cells, injecting it’s genetic material (including healthy gene)
•These cells were injected into the woman’s hepatic portal vein (vein dealing with the liver)
•Some of the cells became part of the woman’s liver, behaving as healthy cells by breaking down cholesterol
•After 2 years, 5% of woman’s liver cells functioned normally, causing blood cholesterol to drop by 20%
•Her cholesterol was twice as high as normal (but manageable)
Hemophilia
- sex-linked disorder; blood is unable to clot because it lacks certain
protein. Recessive gene is carried on the X chromosome - mostly affects males. Severe bleeding.
Duchenne Muscular Dystrophy
- Sex linked disorder; muscle tissue breaks down during childhood due to an inactive form of protein required for normal muscle function.
Recessive gene carried on X chromosome. Few live beyond their teens.
Color -Blindness -
alleles that detect red and green colors are found on the X chromosome. If one of the pigments that help us distinguish these colors is defective, then the person cannot tell the difference between red and green.
Autosomal Recessive Genetic Disorders
• Tay-Sachs Disease
- inherited recessive disorder resulting from a lack of an enzyme that breaks down lipids in the brain. Lipids build up without this enzyme, causing brain damage; appears before the age of one, with death occurring within the first few years of life.
•Phenylketonuria (PKU)
- recessive inherited disorder; enzyme that breaks down phenylalanine is missing. Without this enzyme, phenylalanine breaks down into chemicals that are harmful to the brain. Can be diagnosed by a urine test at birth. A diet low in phenylalanine may avoid brain damage in affected individuals.
•Albinism
– recessive disorder in which the eyes, skin and hair have no pigment. A person with albinism lacks an enzyme needed to produce melanin. People with this condition must take care not to expose themselves to the sun.
Co-dominant Disorder
•Sicke-cell disease
- recessive inherited disorder; red blood cells have abnormal sickle shape causing them to clump, resulting in a lack of oxygen in the blood and pain and weakness.
•Caused by the change of one base of a 300 amino acid chain of hemoglobin: GAA (glutamic acid) to GUA (valine). Most people do not live past childhood. No cure.
•There is a heterozygous advantage in African populations that carry sickle-cellanemia: they are more resistant to malaria.
Incomplete Dominant Disorder
•Familial Hypercholesterolemia (FH) – those who are homozygous recessive have no receptors to take low-density lipoproteins into cells. Therefore their cholesterol is 6X normal, resulting in atherosclerosis and a heart attack by age two.
•Those who are heterozygous for the condition have half the normal amount of receptors,resulting in high (2X) but manageable cholesterol levels.
Heart attack by age 35.
Autosomal Dominant Disorder
•progeria – rare autosomal dominant disorder that causes rapid aging.
•Huntington’s Disease
- Every individual who has the dominant allele develops Huntington’s. Those infected are usually asymptomatic until after 35 years of age. This
disease causes a progressive breakdown of brain cells, leading to death. Symptoms include irritability, memory loss, and loss of muscle coordination.
Objective 2
Genetic Engineering – the process of producing altered DNA, usually by breaking a DNA molecule and inserting new genes.
Objective 3 - The importance of Genetic Counselling (p. 606)
Genetic Counselling – medical professional who consults with the couple to gather information about family history to construct pedigrees.
Helps determine the risk of having a child with a disorder.
•No treatment or cure is known for many inherited disorders.
•Those who may be carriers can be tested and counseled before having children •Inform them of the risks of having affected children; education to help with fears/anxiety
Objective 4 - Detecting Genetic Disorders - p. 607
•Karyotyping - a technique for examining the chromosome makeup of an individual; can detect genetic disorders in a fetus.
•Amniocentesis - a technique used to detect genetic disorders in a fetus; a long needle is used to draw out fluid from the amniotic sac in which the fetus lives; 16th week of pregnancy. Can check for presence or absence of enzymes (Tay
Sachs) or karyotyped to determine if chromosomes are abnormal, missing or extra.
•Chorionic villus sampling
- a technique used by physicians to detect genetic disorders; a sample of the chorion, a part of the placenta is removed for genetic analysis.
Can be done earlier than an amnio.
•Ultrasound high frequency sound waves are reflected off the fetus to produce an image that can be studied to determine the size and position of a developing fetus.
•Fetoscopy - a technique that allows direct observation of the fetus and surrounding tissues by inserting a viewing scope with a special light into the uterus; blood and cell samples may be taken by using tools in addition to the endoscope.
•Genetic markers- any characteristic that provides information about an organism’s genome.
–Linked marker – a known sequence of nucleotides next to a gene that causes a disorder.
–Gene-specific marker – a sequence of DNA that is a part of the gene itself.
–Seeing these sequences shows us that the gene causing a disorder is present. Using a radioactive complementary DNA strand that will attach to the ‘sequence’ in an experimental setting will show scientists that the defective gene is present.
Objective 5 - Treating Genetic Disorders
•Screening and prevention
–Detecting a genetic disorder at birth (Phenylketonuria –PKU)
–Using preventative measures (strict diets) children can grow to lead normal lives
•Surgery –Some conditions can be treated through surgery
–Cleft palate – physical development that results in a groove in the upper lip androof of the mouth. Reconstructive surgery can fix this problem
•Environmental control
–Control the environment in which a person navigates
–Ex. Albinism – lack pigment melanin (no protection against mutagenic effects of sunlight). People with albinism avoid sunlight or wear protective clothing/glasses
•Gene therapy (See pic immedicately below)
–Transferring normal or modified genes into an individual’s defective cells
–In theory, the genes transferred will allow the recipient to begin to synthesize (make) the missing polypeptide, thus reversing the symptoms of the
disorder –Ex. Case in Quebec: Abnormally high cholesterol in blood
•Had heart attack at age 16; bypass by age 26
•Both brothers had died of heart attacks in 20’s
•Patient had 15% of her liver removed
•Healthy human gene she lacked was inserted into the DNA of a harmless virus
•This virus was added to the portion of liver that was removed
•Virus ‘infected’liver cells, injecting it’s genetic material (including healthy gene)
•These cells were injected into the woman’s hepatic portal vein (vein dealing with the liver)
•Some of the cells became part of the woman’s liver, behaving as healthy cells by breaking down cholesterol
•After 2 years, 5% of woman’s liver cells functioned normally, causing blood cholesterol to drop by 20%
•Her cholesterol was twice as high as normal (but manageable)
Objective 6: Techniques Used in Genetic Engineering
page 613-618
Restriction Enzymes(endonucleases) - family of enzymes made by prokaryotic organisms; these enzymes recognize a specific short sequence of nucleotides on a strand of DNA and cut the strand at a particular point (restriction site) within a sequence. (see pic immediately above)
They're specific - the same enzyme will cut a strand of DNA the same way each time
Recombinant DNA - segments of DNA from two species are joined in the laboratory to form a single molecule of DNA.
DNA amplification - the process of generating a large sample of a target DNA sequence from a single gene or DNA sample.
Methods by which this is done:
bacterial vectors - page 615: (see pic) - pic below too
-a restriction enzyme can cleave amphibian DNA on both sides of the target gene.
-the same enzyme cleaves a bacterial plasmid (circular DNA in a bacterium)
-the complimentary ends combine, and DNA ligase seals the DNA
-Now the bacteria has an amphibian gene (recombinant DNA)
-plasmid will reproduce producing the amphibian gene in its DNA
viral vectors - Because a virus can efficiently transport their genomes inside the cells they infect, they can be used to deliver genetic material into
cells. See pic below
Polymerase chain reaction - almost an entirely automated method of replicating DNA that allows researchers to target and amplify a very specific sequence within a DNA sample.
This is how it works p. 615 (see pic)
- DNA, primers and nucleotides are placed into a solution which is heated
-the heat causes the double helix to open; then it's cooled
-heat resistant DNA polymerase is added and the strands are replicated
-the cycle repeats, but because the DNA polymerase is heat resistant, it does not need to be added each time
-billions of copies of the DNA can be produced quickly for analysis
http://www.youtube.com/watch?v=HMC7c2T8fVk – PCR 1:17
Gel electrophoresis -method in which molecules travel through a gel subjected to an electrical circuit. It is used to
separate molecules according to mass and charge, and enables fragments of DNA to be separated for analysis.
This is how it works: pic page 617
-A solution containing fragments of DNA is added to one end of a gel
-the gel then receives an electric current
-the ends of the gel become polarized
-DNA has a negative charge (nucleic 'acid')
-fragments move toward the gel's positive end
-smaller fragments move quicker
-fragments separate into bands, resulting in a DNA fingerprint
http://www.youtube.com/watch?v=o-wh_-tLI70 - ~1 min
DNA sequencing
-chain termination sequencing - process used to sequence DNA. The process relies on a modified form of the PCR
This is how it works - pic page 618
-NA is created but it is in small fragments rather than one strand.
-he nucleotide that ends each fragment is tagged with a radioactive marker
-the fragments are run on a gel
-by looking at the gel, the original DNA strand can be determined.
-Often done with computers as it takes less time
When is all this used?
-to analyze and compare DNA samples (i.e., crime scene, convict or release someone, identify victim)
-disputes over parentage
http://www.youtube.com/watch?v=aPN8LP4YxPo - ~ 1min
page 613-618
Restriction Enzymes(endonucleases) - family of enzymes made by prokaryotic organisms; these enzymes recognize a specific short sequence of nucleotides on a strand of DNA and cut the strand at a particular point (restriction site) within a sequence. (see pic immediately above)
They're specific - the same enzyme will cut a strand of DNA the same way each time
Recombinant DNA - segments of DNA from two species are joined in the laboratory to form a single molecule of DNA.
DNA amplification - the process of generating a large sample of a target DNA sequence from a single gene or DNA sample.
Methods by which this is done:
bacterial vectors - page 615: (see pic) - pic below too
-a restriction enzyme can cleave amphibian DNA on both sides of the target gene.
-the same enzyme cleaves a bacterial plasmid (circular DNA in a bacterium)
-the complimentary ends combine, and DNA ligase seals the DNA
-Now the bacteria has an amphibian gene (recombinant DNA)
-plasmid will reproduce producing the amphibian gene in its DNA
viral vectors - Because a virus can efficiently transport their genomes inside the cells they infect, they can be used to deliver genetic material into
cells. See pic below
Polymerase chain reaction - almost an entirely automated method of replicating DNA that allows researchers to target and amplify a very specific sequence within a DNA sample.
This is how it works p. 615 (see pic)
- DNA, primers and nucleotides are placed into a solution which is heated
-the heat causes the double helix to open; then it's cooled
-heat resistant DNA polymerase is added and the strands are replicated
-the cycle repeats, but because the DNA polymerase is heat resistant, it does not need to be added each time
-billions of copies of the DNA can be produced quickly for analysis
http://www.youtube.com/watch?v=HMC7c2T8fVk – PCR 1:17
Gel electrophoresis -method in which molecules travel through a gel subjected to an electrical circuit. It is used to
separate molecules according to mass and charge, and enables fragments of DNA to be separated for analysis.
This is how it works: pic page 617
-A solution containing fragments of DNA is added to one end of a gel
-the gel then receives an electric current
-the ends of the gel become polarized
-DNA has a negative charge (nucleic 'acid')
-fragments move toward the gel's positive end
-smaller fragments move quicker
-fragments separate into bands, resulting in a DNA fingerprint
http://www.youtube.com/watch?v=o-wh_-tLI70 - ~1 min
DNA sequencing
-chain termination sequencing - process used to sequence DNA. The process relies on a modified form of the PCR
This is how it works - pic page 618
-NA is created but it is in small fragments rather than one strand.
-he nucleotide that ends each fragment is tagged with a radioactive marker
-the fragments are run on a gel
-by looking at the gel, the original DNA strand can be determined.
-Often done with computers as it takes less time
When is all this used?
-to analyze and compare DNA samples (i.e., crime scene, convict or release someone, identify victim)
-disputes over parentage
http://www.youtube.com/watch?v=aPN8LP4YxPo - ~ 1min
Objective 7-10 The Human Genome Project p. 618-20
February 2001 - first published complete draft of human genome
first mammalian genome to be sequenced
-determined the sequence of three billion base pairs
-DNA of all humans is more than 99.9% identical
-differences in people are due to variations in less than 1 in every 1000 nucleotides
-human genome only has 35,000 genes (estimated prior to have 100,000)
-humans produce over 100,000 different proteins
-on average, each gene is capable of synthesizing three different polypeptides
-This project should result in better understanding of connection between what makes up a gene and how the gene functions
-can track nucleotide sequences involved with gene expression
Benefits
-can determine the likelihood of a person developing a disease
-prevent some disorders
-development of better drugs to deal with some genetic conditions
Problems
legal
(employers or insurance companies have access to your genetic information)
ethical
(Tests that can be developed to check for genetic abnormalities or to devise treatments can be great money makers for pharmaceutical
companies)
privacy(should the DNA information be sold to other companies for research? Should a person be informed if his/her genetic information is
shared?)
February 2001 - first published complete draft of human genome
first mammalian genome to be sequenced
-determined the sequence of three billion base pairs
-DNA of all humans is more than 99.9% identical
-differences in people are due to variations in less than 1 in every 1000 nucleotides
-human genome only has 35,000 genes (estimated prior to have 100,000)
-humans produce over 100,000 different proteins
-on average, each gene is capable of synthesizing three different polypeptides
-This project should result in better understanding of connection between what makes up a gene and how the gene functions
-can track nucleotide sequences involved with gene expression
Benefits
-can determine the likelihood of a person developing a disease
-prevent some disorders
-development of better drugs to deal with some genetic conditions
Problems
legal
(employers or insurance companies have access to your genetic information)
ethical
(Tests that can be developed to check for genetic abnormalities or to devise treatments can be great money makers for pharmaceutical
companies)
privacy(should the DNA information be sold to other companies for research? Should a person be informed if his/her genetic information is
shared?)
Biology 3201 – Genetic Implications: Objective 11-14. P. 621-27
A genetically modified organism(GMO) is an organism whose genetic
[material] has been altered using techniques in genetics.
-Techniques generally known as recombinant DNA technology.
-Recombinant DNA technology is the ability to combine DNA molecules from different sources into the one molecule.
-Thus, the phenotype of the organism, can be changed through the modification of its genes.
-transgenic Bt corn, for example, which produces its own insecticide, contains a gene from a bacterium
A genetically modified food is a food product derived in whole or part from a genetically modified organism (GMO) such as a crop plant, animal, or microbe such as yeast. Genetically modified foods have been available since the 1990s.
-Americans are eating genetically modified food without their knowledge. There is not enough research to prove
the safety of inserting genes into fruits, vegetables, and other foods
-Over half the soybean crop, one-third of the corn, and a growing percentage of potatoes grown in the U.S. are genetically modified.
The Food and Drug Administration is considering a ruling that would require genetically engineered food products to be labelled.
While Americans remain fairly quiet on the issue of genetic modification of food, Europeans have loudly opposed biotechnology for several
years. The European Commission has proposed mandatory labeling for genetically modified foods that contain even a single ingredient with one percent genetically modified material
Major significance of these GMO’s and GMF’scorn
-50 types of modified crops approved in Canada
-herbicide resistant corn - resistant to glyphosate
-farmers apply the herbicides without damaging the corn
canola
seeds areengineered to withstand the herbicide Roundup
increased oil production, improve nutritional value
ideal to farmers wishing to produce the largest harvest possible.
MUST BUY THE ENGINEERED SEEDS EVERY YEAR THEY PLANT.
milk
cows exposed to somatotropin at high levels they grow bigger
udders get bigger, producing more milk
rice
golden rice - contains vitamin A, contains higher amounts of iron
higher nutrients... reduce vitamin A and iron deficiencies in developing countries
transgenic salmon·
Genetically modified salmon are on track to become the first commercially developed animals approved for human consumption.
Salmon are genetically engineered to increase/accelerate growth rates, improve flesh color and increase disease resistance. The ability to make these changes decreases production costs, increases the consumer appeal of the product, and ultimately increases profits. ·
problems: escaping and mating with wild salmon
insulin producing bacteria
insulin synthesized by transgenic (genetically engineered) bacteria
before then, extracted from cows and pigs – allergic reactions
higher amounts of insulin, lowered costs and side effects
PCB eating bacteria
bacteria degrade harmful PCB’s into harmless compounds
PCBs build up in soil and accumulate in food chain
PCBs - polychlorinated biphenyls - by-products from industry
using living cells to repair the environment - bioremediation
oil eating bacteria
bacteria can clean up oil spills
some bacteria can obtain energy from substances that would poison other organisms
Environmental threats
•use of herbicide resistant crops may cause farmers to use more herbicide (more going
into the ground and water)
•GMO genes can spread accidentally to wild plants, harming biodiversity
•risk of herbicide resistant plants crossing with weeds to cause ‘superweeds’, making them hard to control
•same goes for insects: ‘superbugs’
Health Effects
•not enough is known about long term effects of transgenic products
•may have effects that do not appear until later or do not show up in research.
•GMOs may find their way into our foods when they aren’t approved for human consumption
Social and Economic Issues
•crops may help to alleviate world hunger
•opponents argue that world hunger is result of unequal food distribution, not food shortages
•world food supplies may become dominated by private companies that create GMOs
•smaller farms go out of business because of large scale farming favored.
In summary - Things to think about...
•Should GMO’s and GMF’s NEVER be used?
•Enough info about benefits/effects?
•Hunger problems – distribution; not a LACK of food.
•Is spending money on GMO/GMF research to create these foods the right way to offer foreign help?
•Effects of interbreeding GMO’s with natural organisms – damage/wipeout native species?
•Complications from consuming GMO’s and GMF’s?
A genetically modified organism(GMO) is an organism whose genetic
[material] has been altered using techniques in genetics.
-Techniques generally known as recombinant DNA technology.
-Recombinant DNA technology is the ability to combine DNA molecules from different sources into the one molecule.
-Thus, the phenotype of the organism, can be changed through the modification of its genes.
-transgenic Bt corn, for example, which produces its own insecticide, contains a gene from a bacterium
A genetically modified food is a food product derived in whole or part from a genetically modified organism (GMO) such as a crop plant, animal, or microbe such as yeast. Genetically modified foods have been available since the 1990s.
-Americans are eating genetically modified food without their knowledge. There is not enough research to prove
the safety of inserting genes into fruits, vegetables, and other foods
-Over half the soybean crop, one-third of the corn, and a growing percentage of potatoes grown in the U.S. are genetically modified.
The Food and Drug Administration is considering a ruling that would require genetically engineered food products to be labelled.
While Americans remain fairly quiet on the issue of genetic modification of food, Europeans have loudly opposed biotechnology for several
years. The European Commission has proposed mandatory labeling for genetically modified foods that contain even a single ingredient with one percent genetically modified material
Major significance of these GMO’s and GMF’scorn
-50 types of modified crops approved in Canada
-herbicide resistant corn - resistant to glyphosate
-farmers apply the herbicides without damaging the corn
canola
seeds areengineered to withstand the herbicide Roundup
increased oil production, improve nutritional value
ideal to farmers wishing to produce the largest harvest possible.
MUST BUY THE ENGINEERED SEEDS EVERY YEAR THEY PLANT.
milk
cows exposed to somatotropin at high levels they grow bigger
udders get bigger, producing more milk
rice
golden rice - contains vitamin A, contains higher amounts of iron
higher nutrients... reduce vitamin A and iron deficiencies in developing countries
transgenic salmon·
Genetically modified salmon are on track to become the first commercially developed animals approved for human consumption.
Salmon are genetically engineered to increase/accelerate growth rates, improve flesh color and increase disease resistance. The ability to make these changes decreases production costs, increases the consumer appeal of the product, and ultimately increases profits. ·
problems: escaping and mating with wild salmon
insulin producing bacteria
insulin synthesized by transgenic (genetically engineered) bacteria
before then, extracted from cows and pigs – allergic reactions
higher amounts of insulin, lowered costs and side effects
PCB eating bacteria
bacteria degrade harmful PCB’s into harmless compounds
PCBs build up in soil and accumulate in food chain
PCBs - polychlorinated biphenyls - by-products from industry
using living cells to repair the environment - bioremediation
oil eating bacteria
bacteria can clean up oil spills
some bacteria can obtain energy from substances that would poison other organisms
Environmental threats
•use of herbicide resistant crops may cause farmers to use more herbicide (more going
into the ground and water)
•GMO genes can spread accidentally to wild plants, harming biodiversity
•risk of herbicide resistant plants crossing with weeds to cause ‘superweeds’, making them hard to control
•same goes for insects: ‘superbugs’
Health Effects
•not enough is known about long term effects of transgenic products
•may have effects that do not appear until later or do not show up in research.
•GMOs may find their way into our foods when they aren’t approved for human consumption
Social and Economic Issues
•crops may help to alleviate world hunger
•opponents argue that world hunger is result of unequal food distribution, not food shortages
•world food supplies may become dominated by private companies that create GMOs
•smaller farms go out of business because of large scale farming favored.
In summary - Things to think about...
•Should GMO’s and GMF’s NEVER be used?
•Enough info about benefits/effects?
•Hunger problems – distribution; not a LACK of food.
•Is spending money on GMO/GMF research to create these foods the right way to offer foreign help?
•Effects of interbreeding GMO’s with natural organisms – damage/wipeout native species?
•Complications from consuming GMO’s and GMF’s?
Objective 15-17: Cloning. P. 627-30
Cloning is creating an identical copy of an organism or part of an organism that has the same genetic make up, such as the offspring of asexual reproduction.
•Identical Twins are natural clones of each other.
•Cloning can be done today by removing the nucleus from an egg cell and replacing itwith another, then growing and implanting the cell.
•The result (offspring) will be identical to the donator of the new nucleus to the cell.
•Dolly the Sheep, perhaps the most famous known clone in existence was created through this method.
How Dolly was cloned:
•unfertilized eggs collected from a donor animal.
•the nuclei of these cells are removed, and replaced with cells collected from the udder of another sheep (cells stopped in G phase of interphase. This stopped “growth”.)
•an electrical current is applied to stimulate the cell cycle
•the resulting cells are cultured and embryos are collected and implanted into the surrogate mother
•the embryo that survives makes a baby lamb that is genetically identical to the donor of the udder cell.
•From the evidence that has been collected from several cloned animals, proof has begun to surface about the danger of cloning.
•Dolly the sheep had shown signs of premature aging, and also had arthritis.
•She was put down in 2003 – virus-induced lung disease (immune issues)
•Researchers have discovered that cloned animals have difficulties associated with gene expression.
•Other Risks of Cloning:
–Destruction of 100’s of embryos – change society’s definition of ‘life’?
–Premature aging
–Arthritis
•Benefits of Cloning:
–Eliminate all human disease?
–Be your own donor
http://www.youtube.com/watch?v=YoEWYJHf0kU – 2 mins
http://www.youtube.com/watch?v=tELZEPcgKkE – 14 mins
Objective 18 - Careers related to Biotechnology
•Cytogeneticist: a geneticist who detects and analyses hereditary diseases and abnormalities. This is achieved by studying chromosomes that have been obtained from samples of blood, bone marrow, etc
•Medical geneticist - trained in general medicine, genetic diagnosis, and the treatment of patients with genetic disorders.
•Genetic Engineer – a person who uses technology to removeor add elements of an organism's genetic makeup, or even transfer DNA from one
species to another.
Cloning is creating an identical copy of an organism or part of an organism that has the same genetic make up, such as the offspring of asexual reproduction.
•Identical Twins are natural clones of each other.
•Cloning can be done today by removing the nucleus from an egg cell and replacing itwith another, then growing and implanting the cell.
•The result (offspring) will be identical to the donator of the new nucleus to the cell.
•Dolly the Sheep, perhaps the most famous known clone in existence was created through this method.
How Dolly was cloned:
•unfertilized eggs collected from a donor animal.
•the nuclei of these cells are removed, and replaced with cells collected from the udder of another sheep (cells stopped in G phase of interphase. This stopped “growth”.)
•an electrical current is applied to stimulate the cell cycle
•the resulting cells are cultured and embryos are collected and implanted into the surrogate mother
•the embryo that survives makes a baby lamb that is genetically identical to the donor of the udder cell.
•From the evidence that has been collected from several cloned animals, proof has begun to surface about the danger of cloning.
•Dolly the sheep had shown signs of premature aging, and also had arthritis.
•She was put down in 2003 – virus-induced lung disease (immune issues)
•Researchers have discovered that cloned animals have difficulties associated with gene expression.
•Other Risks of Cloning:
–Destruction of 100’s of embryos – change society’s definition of ‘life’?
–Premature aging
–Arthritis
•Benefits of Cloning:
–Eliminate all human disease?
–Be your own donor
http://www.youtube.com/watch?v=YoEWYJHf0kU – 2 mins
http://www.youtube.com/watch?v=tELZEPcgKkE – 14 mins
Objective 18 - Careers related to Biotechnology
•Cytogeneticist: a geneticist who detects and analyses hereditary diseases and abnormalities. This is achieved by studying chromosomes that have been obtained from samples of blood, bone marrow, etc
•Medical geneticist - trained in general medicine, genetic diagnosis, and the treatment of patients with genetic disorders.
•Genetic Engineer – a person who uses technology to removeor add elements of an organism's genetic makeup, or even transfer DNA from one
species to another.