Genetic Disorders And Diseases

Summary

This transcript delves into the profound impact of genetic mutations on human health, illustrating how minor changes in DNA can lead to severe conditions like cystic fibrosis and Tay-Sachs disease. It explores the potential of gene therapy to correct these mutations, with examples of treating SCID and muscular dystrophy. Additionally, it touches on the ethical implications of genetic selection in IVF, raising questions about the future of genetic engineering in determining our children's traits.

Takeaways

• 🧬 The gene on chromosome 7 with 6,129 active letters codes for a protein that allows salt to penetrate membranes, and a tiny mutation can lead to cystic fibrosis.
• 🌐 A single-letter mutation in a gene can have significant consequences, as seen in TSC disease, which causes fatal brain swelling due to a protein malfunction.
• 🔍 The US government's chromosome viewer website provides information on genes, chromosomes, and associated traits and disorders.
• 🧬 Genetic diseases like breast cancer can be inherited due to mutations in genes, which can be identified and tracked through genetic sequencing.
• 🩺 Gene therapy is an emerging field that can correct genetic mutations, such as in SCID, by inserting normal genes into a patient's DNA.
• 💊 Protein therapy is an alternative to gene therapy, focusing on supplying correctly formed proteins to patients with genetic disorders.
• 🐀 Research has shown success in treating muscular dystrophy in rats using gene therapy to restore the production of a crucial protein.
• 🐐 Genetic modification has been used to create animals, like goats, that produce milk containing human proteins for medical use.
• 👨‍👩‍👧‍👦 The script raises ethical questions about genetic selection and engineering in humans, such as choosing traits for children through in vitro fertilization.
• 🧐 The technology discussed highlights the potential for both curing genetic diseases and the controversial ability to select desired traits in offspring.

Q & A

What is the function of the protein encoded by the gene on chromosome 7 mentioned in the script?

The protein encoded by the gene on chromosome 7 allows salt to penetrate various membranes in the body, specifically by inserting itself into the plasma membrane and creating a passageway for salts to enter and leave the cells.

What is the consequence of the tiny mutation in Susan's gene on chromosome 7?

The mutation causes the protein to be slightly misshapen, which prevents it from properly transporting through the plasma membrane. This leads to salt getting trapped inside cells, causing the cell surface to become sticky and covered with thick mucus, resulting in cystic fibrosis.

What is the genetic cause of TAC disease as described in the script?

TAC disease is caused by an error in a gene that results in a protein not functioning properly to dissolve fatty materials in the brain. This leads to a buildup of fat, swelling of the brain, and eventual damage to critical brain cells.

How does the script explain the impact of a single genetic mutation on an individual's health?

The script illustrates that even a single genetic mutation, such as a missing letter in a gene, can have significant health consequences, as seen in the examples of cystic fibrosis and TAC disease.

What is gene therapy and how does it relate to the diseases mentioned in the script?

Gene therapy is a promising technology that involves fixing broken genes. It can be used to treat diseases like SCID by inserting a normal gene into a patient's DNA, either replacing the faulty gene or coexisting with it, allowing the production of normal disease-fighting cells.

How does the script describe the potential of gene therapy in treating muscular dystrophy?

The script describes gene therapy's potential in treating muscular dystrophy by using a harmless virus to transmit the missing gene to every muscle in the body, reversing the muscle wasting characteristic of the disease.

What is protein therapy and how does it differ from gene therapy?

Protein therapy involves artificially creating the correct form of a misshapen protein and injecting it into the patient. It differs from gene therapy in that it does not require identifying the specific genetic errors causing the protein to be misshapen; instead, it focuses on supplying the correct protein shape.

How does the script suggest genetic modification can be used to produce therapeutic proteins?

The script provides an example of a genetically modified goat whose milk contains a human protein that can be extracted for patients who cannot manufacture it themselves, demonstrating the potential of genetic modification for therapeutic protein production.

What ethical considerations are raised by the script regarding the selection of genetic traits for offspring?

The script raises ethical considerations about the implications of choosing specific genetic traits for offspring, such as the potential for eliminating undesirable traits and the idea of giving children the 'best possible start' through genetic selection.

What resource does the script mention for obtaining information about genes, chromosomes, and proteins?

The script mentions a US government website with current information about genes, chromosomes, and proteins, including a chromosome viewer section where users can select a chromosome and see associated traits and disorders.

Outlines

00:00

🧬 Genetic Mutations and Their Impact

This paragraph discusses the significant effects of minor genetic mutations on human health. It uses the example of a gene on chromosome 7, which, when mutated, can lead to cystic fibrosis due to a misshapen protein that fails to transport salt across cell membranes, causing mucus build-up and respiratory issues. It also mentions Tay-Sachs disease, caused by a single-letter mutation that leads to a protein malfunction, resulting in the accumulation of fatty materials in the brain and severe neurological deterioration. The paragraph highlights the inheritable nature of these mutations and directs viewers to a government website for more information on genes, chromosomes, and proteins.

05:01

🧬 Gene Therapy and Genetic Selection

The second paragraph explores gene therapy as a promising approach to treating genetic disorders. It describes how gene therapy can correct genetic mutations, such as in SCID, by introducing normal genes into a patient's DNA, allowing the production of disease-fighting cells. Another example is muscular dystrophy, where gene therapy using a harmless virus can reverse muscle wasting by delivering the missing gene. The paragraph also discusses protein therapy as an alternative to gene therapy, which involves supplying correctly formed proteins to patients. Additionally, it touches on the ethical implications of genetic selection in reproduction, where parents can choose traits for their children, such as physical appearance and intelligence, raising questions about the best approach to genetic inheritance.

Keywords

💡Chromosome

A chromosome is a structure within cells that contains genetic information in the form of DNA. In the context of the video, chromosome 7 is specifically mentioned as the location of a gene that, when mutated, can lead to cystic fibrosis. This example illustrates how genetic information is organized and inherited, and how mutations can result in disease.

💡Gene

A gene is a segment of DNA that contains instructions for the production of proteins, which are essential for the function and development of an organism. The video script discusses a gene with 6,129 active letters that, when functioning correctly, produces a protein allowing salt to penetrate membranes. It also mentions a gene on chromosome 7 associated with cystic fibrosis, highlighting the role of genes in health and disease.

💡Amino Acids

Amino acids are the building blocks of proteins. The video describes how a gene strings together 1,480 amino acids to form a protein. This process is critical for the protein's structure and function, as exemplified by the misshapen protein in cystic fibrosis, which cannot perform its intended role due to a mutation in the gene.

💡Protein

Proteins are large molecules composed of amino acids and are essential for various functions in the body, including catalyzing biochemical reactions, providing structural support, and transporting molecules. The video explains how a protein's shape is crucial for its function, as seen in the case of cystic fibrosis where a slight protein misshape leads to severe health consequences.

💡Cystic Fibrosis

Cystic fibrosis is a genetic disorder caused by a mutation in a gene on chromosome 7. The video describes how a tiny error in this gene leads to a misshapen protein that cannot transport salt across cell membranes, resulting in thick mucus buildup in the lungs and other organs. This term is central to the video's theme of how genetic mutations can impact health.

💡Mutation

A mutation is a change in the DNA sequence that can lead to alterations in the structure or function of a gene. The video script uses the example of a tiny mutation in the gene on chromosome 7 causing cystic fibrosis, illustrating how mutations can have significant effects on an individual's health.

💡Gene Therapy

Gene therapy is a medical technique that involves altering or replacing a person's genes to treat or prevent disease. The video mentions gene therapy as a promising approach for diseases like SCID, where a normal gene is inserted into a patient's DNA to correct a mutation. This concept is central to the video's exploration of modern medical advancements.

💡Protein Therapy

Protein therapy involves artificially creating and delivering the correct form of a misshapen protein to patients who cannot produce it themselves. The video gives an example of a genetically modified goat whose milk contains a human protein that can be extracted for therapeutic use. This concept is discussed in the context of alternative approaches to gene therapy.

💡Genetic Counselor

A genetic counselor is a professional who helps individuals understand and adapt to the medical, psychological, and familial implications of genetic contributions to disease. In the video, Greg and Marie receive genetic counseling regarding their in vitro fertilization, highlighting the role of genetic counselors in the era of genetic technology.

💡In Vitro Fertilization (IVF)

In vitro fertilization is a process where eggs and sperm are fertilized outside the body, and the resulting embryos can be screened for genetic disorders before implantation. The video script describes a scenario where Greg and Marie select traits for their child through IVF, showcasing the ethical and practical considerations of genetic selection.

Highlights

A gene on chromosome 7 with 6,129 active letters codes for a protein that allows salt to penetrate membranes.

A tiny error in Susan's gene on chromosome 7 causes a misshapen protein leading to cystic fibrosis.

Cystic fibrosis results from salt getting trapped inside cells due to a misshapen protein.

Tay-Sachs disease begins with a single DNA letter error causing a protein malfunction that leads to brain damage.

A single genetic mistake can lead to the accumulation of fat in the brain and eventual cell death.

Genetic diseases can be inherited, as seen with mutations causing breast cancer.

The US government maintains a website with current information about genes, chromosomes, and proteins.

Chromosome viewer allows users to see the number of base pairs on a chromosome and associated traits.

Gene therapy is a promising technology for fixing broken genes, such as in SCID.

In gene therapy for SCID, a normal gene is inserted into a patient's DNA to produce normal cells.

Muscular dystrophy can be treated with gene therapy using a virus to transmit the missing gene.

Protein therapy involves creating the correct protein form and injecting it into patients.

Scientists have genetically modified goats to produce milk containing a human protein for medical use.

Gene selection technology allows parents to choose their children's genetic traits.

Parents are given the option to select the best traits for their children through genetic counseling.

The potential for gene therapy and selection raises ethical questions about designer babies.

Transcripts

somewhere on chromosome 7 there is a

gene that has

6,129 active letters in it this Gene

strings together

1,480 amino acids into a protein whose

function is to allow salt to penetrate

various membranes in the

body little Susan has a tiny era in that

Gene in her seventh

chromosome three letters are

missing and that causes the protein that

Susan's genes manufacture to be ever so

slightly

misshapen and although the difference in

the shape is Tiny the consequences are

huge this particular protein does its

work in the Linings of the

lungs by inserting itself into the

plasma membrane the protein makes a

passageway for the salts to enter and

leave the cells

but if the protein is not exactly the

right shape then it cannot transport the

plasma membrane and therefore cannot do

its

job then salt gets trapped inside the

cell and that causes the cell surface to

become sticky and covered with thick

mucus this results in wheezing

breathlessness in the persistent cough

to expel Troublesome

mucus this is cystic fibrosis and it is

the result of just three missing letters

on chromosome

7 perhaps even more tragic is tasac

disease tasac begins at one infant tmal

spot on the DNA ladder when just one

letter goes

wrong this mistake comes down to just

four

atoms that's it but the error in that

Gene creates a problem in this protein

which is supposed to dissolve fatty

materials in the

brain but now the protein doesn't

work so fat builds up swells the brain

and eventually strangles and crushes the

critical brain

cells infants with Tac disease appear to

develop normally for the first few

months of

life then as nerve cells become

distended with fatty

materials a Relentless deterioration of

mental and physical abilities

occur the child becomes blind deaf and

unable to

swallow muscles begin to atrophy and

paralysis sets

in hard to imagine that just four wrong

atoms change just one letter out of 3

billion and this is the

result when genetic diseases run through

families then we know the mutations in

the genes that cause these diseases are

being inherited here is an example in a

normal Gene this is the sequence ending

g t a g c a g t

but sometimes the gene is missing two of

the

letters this new configuration is a

mutation that can often lead to breast

cancer and it is passed from generation

to

generation causing the potential for

disease to be passed down as

[Music]

well the US government maintains a

website with much of the current

information about genes chromosomes and

proteins

in the section labeled chromosome viewer

you can select a chromosome and see how

many base pairs or letters are on the

chromosome when you get to the web page

for each particular chromosome you can

see a list of traits and disorders

associated with genes on that

chromosome let's enlarge chromosome 7

that we talked about

earlier as you can see the gene that

causes Cystic Fibrosis is

here

on other Pages you can see genetic

disease

profiles here is the cystic fibrosis

profile you can even examine specifics

about some

genes again this page details genes

associated with cystic

fibrosis how can we fix genes that are

broken gene therapy is a new and

promising

technology consider a disease like

scid which is an autoimmune disease

caused by single gene mutation which

prevents the body from producing normal

disease fighting

cells these patients have no natural

defense and often spend their lives in

an isolation bubble to prevent contact

with other

people since bone marrow is the place

where cells are made which normally

defend the body

bone marrow is drawn from the patient

and a normal Gene is inserted into the

patient's DNA either replacing the

faulty gene or coexisting with

it then these repaired marrow cells are

placed back into the patient's body

where they begin to multiply and produce

normal disease fighting

[Music]

cells another example of promising gene

therapy involves muscular distrophy

muscular destrophy is a genetic disorder

characterized by insufficient production

of a protein called

disten diseased victims muscles

eventually weaken to the point where

they cannot

survive researchers studying distrophy

in rats have successfully used a

harmless virus to transmit the missing

Gene to every muscle of the rat's body

reversing the muscle wasting that

characterizes the

disease

this is a magnified image of the

quadriceps muscle of a normal

Mouse the distene protein is shown in

green and outlines the cells in the

muscle this is a similar image of the

mouse victimized by muscular distrophy

and this remarkable image shows a muscle

in that same Mouse 6 weeks after the

gene

[Music]

therapy

protein therapy is similar but instead

of fixing a patient's genes it is

directed at artificially creating the

correct form of the misshape and protein

and injecting these correctly form

proteins directly into the

patient this may prove to be easier in

the short term because we don't have to

identify the specific genetic errors

that cause the protein to be misshapen

in the first place

we only have to supply the proteins that

have the correct

[Music]

shape scientists have successfully

produced a goat that has been

genetically modified so that her milk

contains a human protein that can be

extracted and given to patients who

cannot manufacture it

[Music]

themselves but in addition to curing

diseases we are also developing the

skill to choose which of our genes our

children will

[Music]

receive Greg and Marie are about to hear

the results of their invitro

fertilization from their genetic

counselor they are about to face the

full implications of this emergent

technology your extracted ex Maria have

been genetically matched in vitro with

Greg

sperm now you've selected a boy with

blue eyes brown hair and fair

skin as an adult he'll be 5T 11 in tall

and his IQ will be near genius

level now I've taken the liberty of

eliminating a few undesirable traits

alcoholism cancer

Alzheimer's B this obesity well I

thought certainly no diseases but we

were wondering if we shouldn't leave

some characteristics to

chance you want to give your child the

best possible sge remember this child is

still you simply the best of you you

could conceive naturally a thousand

times and still never get such a

result I'll give you a minute to think

about

it should we choose the best that's in

us for our

children