Blood Types

Summary

In this educational podcast, Mr. Andersen delves into the significance of blood typing in modern medicine, focusing on the ABO system and the Rh factor. He explains the presence of proteins on erythrocytes and the antibodies' role in immune response, emphasizing the importance of matching blood types during transfusions. The podcast also covers the genetic basis of blood types, including multiple alleles and codominance, and touches on the implications of the Rh factor in pregnancy and blood donation, highlighting the rarity of certain blood types and their historical significance in tracing human ancestry.

Takeaways

• 🌟 Blood typing is crucial in modern medicine for safe blood transfusions, which was not a concern in ancient times.
• 🔬 The ABO blood typing system and the Rh factor are the primary blood types discussed, with over 30 other families of blood types existing.
• 🌱 Blood types refer to specific proteins or glycoproteins on the surface of erythrocytes, which differ among ABO blood groups.
• 🔄 Individuals with type A blood have A antigens and B antibodies, type B has B antigens and A antibodies, type AB has both A and B antigens with no antibodies, and type O has neither antigen but has both A and B antibodies.
• ⚠️ The immune response is critical in blood transfusions; mismatched blood types can lead to a severe reaction due to antibodies attacking foreign antigens.
• 💉 Type O blood can be safely given to any blood type due to the absence of antigens, making type O the universal donor.
• 🏥 Type AB blood can receive blood from any type, known as the universal recipient, because it lacks antibodies that would attack the antigens.
• 🧬 Blood type genetics involve multiple alleles and codominance, with six different genotypes possible for the four phenotypes (A, B, AB, O).
• 🤰 Rh factor genetics is simpler, with individuals being either Rh positive (having the Rh proteins) or Rh negative (lacking them), and Rh+ being dominant.
• 👶 Incompatibilities in Rh factor during pregnancy can lead to complications like hemolytic disease in the fetus if the mother is Rh- and the baby is Rh+.
• 📊 Blood type distribution varies among populations, with O+ being the most common and some rare blood types like AB- found in less than 1% of individuals.

Q & A

What is the significance of blood typing in modern medicine?

Blood typing is crucial in modern medicine primarily due to its role in blood transfusions. It helps ensure that the blood transfused is compatible with the recipient's blood type, preventing adverse immune reactions.

What are the two main blood type systems discussed in the podcast?

The two main blood type systems discussed are the ABO blood typing system and the Rh factor.

How many different blood type families are there in total?

There are about 30 different families of blood types, in addition to the ABO and Rh systems.

What are the proteins found on the surface of blood cells called?

The proteins found on the surface of blood cells are called glycoproteins.

What does it mean to have type A blood?

Having type A blood means that the individual's blood cells have an A protein on their surface.

What are the implications of having type AB blood?

Type AB blood is significant because individuals with this blood type have both A and B proteins on their blood cells, making them universal recipients, capable of receiving blood from any blood type.

Why is it important to match blood types during a blood transfusion?

Matching blood types is essential to prevent the recipient's antibodies from attacking the transfused blood, which can lead to severe reactions or even death.

What is the role of antibodies in the ABO blood type system?

Antibodies in the ABO system are designed to protect the body against invasion by matching and attacking foreign blood cells with different antigens. Each blood type has specific antibodies that do not attack its own blood cells.

How does the Rh factor differ from the ABO blood type system in terms of genetics?

The Rh factor is simpler genetically because it involves the presence or absence of Rh proteins. Rh positive individuals may be homozygous or heterozygous, while Rh negative individuals are always homozygous negative.

What is the significance of O- blood type in blood transfusions?

O- blood type is considered the universal donor because it can be given to individuals of any blood type without causing an immune reaction. However, only about 6.6% of the population has this blood type.

How can blood typing help trace human ancestry?

The presence or absence of certain blood proteins, like the B protein in some native populations, can provide insights into human migration and ancestry, as these proteins can be traced back to specific geographical regions.

Outlines

00:00

🩸 ABO Blood Typing and Its Importance

Mr. Andersen introduces the concept of blood typing, emphasizing its significance in modern medicine for blood transfusions. He explains the ABO blood typing system, detailing the presence of A, B, or both antigens (A and B proteins) on the surface of erythrocytes for types A, B, and AB respectively, and the absence of these antigens for type O. He also discusses the corresponding antibodies each blood type possesses, highlighting the importance of matching blood types during transfusions to prevent immune reactions. Mr. Andersen mentions the evolutionary aspect of blood types and the complexity of understanding the genetic basis behind them.

05:03

🧬 Blood Type Genetics and Rh Factor

This paragraph delves into the genetic aspect of blood typing, explaining the concept of phenotypes and genotypes. Mr. Andersen clarifies that while there are four blood type phenotypes (A, B, AB, O), there are six possible genotypes, including homozygous and heterozygous variations for types A and B, and the necessity of having both A and B alleles for type AB. He also introduces the Rh factor, a simpler genetic system with either the presence or absence of Rh antigens, and discusses the potential complications of an Rh-negative mother carrying an Rh-positive child, which could lead to the mother developing antibodies against the Rh factor during subsequent pregnancies.

10:09

🌐 Blood Type Distribution and Historical Significance

In the final paragraph, Mr. Andersen discusses the distribution of blood types within the population, noting the rarity of certain types like AB- and the prevalence of O+ and A+. He also touches on the historical and geographical distribution of blood types, using the example of native populations like Australian Aborigines and Native Americans where type B was not present before the arrival of Europeans. This distribution can provide insights into human ancestry. The paragraph concludes with a brief mention of the practical implications of blood typing in blood donation and transfusion, identifying O- as the universal donor and AB+ as the universal recipient.

Keywords

💡Blood Typing

Blood typing is the classification of blood based on the presence or absence of antigenic substances on red blood cells. It is crucial in modern medicine for safe blood transfusions. In the script, Mr. Andersen discusses the importance of ABO blood typing and the Rh factor, emphasizing their role in determining compatibility for transfusion, which is central to the video's theme of understanding blood compatibility.

💡ABO Blood Typing

ABO blood typing is a system that classifies human blood into four groups based on the presence of A, B, or both (AB) antigens on the surface of red blood cells, or none (O). The script explains that individuals with type A blood have A antigens and B antibodies, while type B individuals have the opposite. Type AB has both antigens, and type O has neither, which is vital for avoiding immune reactions during transfusions.

💡Rh Factor

The Rh factor is a protein found on the surface of red blood cells, which can be either present (Rh+) or absent (Rh-). It is significant in the context of blood transfusions and pregnancy, as the script mentions. The Rh factor's genetics are simpler than ABO typing, with the presence of the factor being dominant, and its absence being recessive.

💡Antigens

Antigens are substances that can trigger an immune response, such as the proteins on the surface of red blood cells in the ABO system. In the script, Mr. Andersen describes how individuals with type A blood have A antigens and corresponding B antibodies, which is a fundamental concept in understanding blood typing and immune reactions.

💡Antibodies

Antibodies are proteins produced by the immune system to identify and neutralize foreign objects like bacteria and viruses. In the context of blood typing, the script explains that individuals have antibodies for blood antigens they do not possess, which is critical for preventing adverse reactions during blood transfusions.

💡Erythrocytes

Erythrocytes, commonly known as red blood cells, are the most common type of blood cell and are the focus of blood typing. The script mentions erythrocytes as the cells that have antigens on their surface, which determine a person's blood type.

💡Immune Response

The immune response is the body's defense mechanism against foreign substances. In the script, Mr. Andersen explains how the immune system's response to foreign blood antigens can lead to severe reactions, making blood typing essential for safe transfusions.

💡Universal Donor

A universal donor is someone who can donate blood to any blood type. In the script, O- blood is identified as the universal donor because it lacks A, B, and Rh antigens, which makes it safe for transfusions to recipients of any ABO or Rh type.

💡Universal Recipient

A universal recipient is someone who can receive blood from any blood type. The script identifies AB+ as the universal recipient due to the absence of antibodies for A, B, or Rh antigens, allowing them to receive blood from any donor without adverse reactions.

💡Genetics

Genetics refers to the study of genes, genetic variation, and heredity in organisms. In the script, Mr. Andersen discusses the genetic basis of blood types, explaining how different genotypes can result in the same phenotype and the importance of understanding these genetic principles for solving blood typing problems.

💡Punnett Square

A Punnett square is a diagram used to predict the genotypes of offspring from a particular cross. In the script, Mr. Andersen uses Punnett squares to illustrate how the combination of parental genotypes can result in different blood types for their children, which is essential for understanding genetic inheritance of blood types.

Highlights

Blood typing is crucial in modern medicine due to the need for blood transfusions.

ABO blood typing and Rh factor are the primary blood type systems discussed.

There are approximately 30 other families of blood types beyond ABO and Rh.

Blood types refer to proteins on the surface of erythrocytes.

Type A blood has A proteins, type B has B proteins, type AB has both, and type O has none.

Antibodies are present against non-self blood proteins, except for one's own blood type.

Type A blood has B antibodies, type B has A antibodies, type AB has no antibodies, and type O has both A and B antibodies.

Type O blood can be safely transfused to any blood type due to the absence of surface proteins.

Transfusing type B blood to a type A individual can be fatal due to antibody reactions.

Type AB is considered the universal recipient, as it can receive blood from all types.

Type O blood is the universal donor, but can only receive type O blood due to antibodies.

Understanding blood type genetics is essential for solving genetic problems related to blood.

There are four phenotypes (A, B, AB, O) and six genotypes in the ABO blood system.

Type A or B blood can be homozygous or heterozygous, while type AB must be heterozygous.

Rh factor genetics are simpler, with Rh+ being dominant and Rh- being recessive.

Rh- individuals can develop antibodies against Rh+ blood, especially during subsequent pregnancies.

O- blood is the universal donor, and AB+ is the universal recipient.

Blood type distribution varies among different populations, reflecting genetic history.

Transcripts

Hi. It's Mr. Andersen and in this podcast I'm going to talk about blood

types. Blood typing wasn't that big of deal back in the day because when we were cavemen

it didn't really exist this whole idea of transfusing blood from one person to another.

But with modern medicine it's actually becoming a really big deal. Now you should know this.

In humans the ones I'll talk about in this podcast are going to be the ABO blood typing.

And another one I'll talk about is the Rh factor. But know this, that there are about

another 30 other families of blood types. And what are we talking about when we're talking

about blood types? Well basically we're talking about proteins that are found on the surface

of our blood cells. Or our erythrocytes. And so basically if we're looking at the ABO system

if you are type A blood, which I happen to be type A blood. That means that you're going

to have an A protein or a specific protein on the surface of your blood. If you are type

B blood then you're going to have a B protein on the surface of your blood. And this is

just a comic version. They're going to be really, really tiny. You wouldn't be able

to see them. They're just little proteins on the surface. Or glycoproteins that are

found on the surface of the blood. So if you think about it what if you're type AB blood?

Well basically that means that you have both types of proteins. And if you're type O that

means that you have none of these specific proteins that are found on your blood. And

so each of these have arisen through our evolutionary history. But they actually are really important

when we're trying to move blood from one person to another. And that's because of our immune

response. And so if you're type A blood, and so let's remember that that's that purple

kind of a protein, that pointy purple protein. Well basically you're going to have that type

of blood. But you're going to have antibodies for the other type, the B antibody we call

that. And the reason why is that you have antibodies for every shape possible except

the shape that you actually have. And so we're not going to have purple antibodies. But we're

going to have these B antibodies. And that's just because we don't have the B protein around.

Likewise if we look at type B blood. It's going to have the B proteins but it would

be silly for us to have those B antibodies because it would just simply attack our own

blood. But instead we're going to have the type A antibodies. If we look at somebody

who's type AB blood. Well, since they have both of these antigens or both of these proteins

on their surface, A and B, then we really wouldn't want to have any other antibodies

because again they would attack our blood. And then finally if you're type O, basically

if you're type O, since you don't have either of the these proteins, then you're going to

have antibodies that match up that specific shape. And so again, the antibodies are there

simply to protect our body against invasion or against invaders. And so now let's look

at type A. Let's say you're type A blood. And so we said we got the purple pointy proteins.

You're going to have the B antibodies. Let's say that we give that person type O blood.

Well what's going to happen? Well since there are no proteins on its surface nothing will

happen. So it's okay to transfer type O blood to somebody who is type A. Nothing happens.

But let's say we give them type B blood. Well that type B blood is going to have the B proteins

and so basically those B antibodies are going to grab onto it. They're going to attack that.

And we could die as a result of that. And that's why it's important that when we're

giving somebody blood transfusion we make sure that we type their blood. Because otherwise

their antibodies are going to attack it. Let's say now we've got type B blood. Again, we've

got the A antibodies, let's say we give that person A blood. Well you can probably figure

this out. Basically all of those antibodies are going to glom on to that type A blood.

And so we could die as a result of that. Now let's look at somebody who has type AB blood.

Well let's give them type A blood. Well since they have no antibodies, at least for this

protein, nothing would happen. Or if we give them type B blood, nothing will happen. Or

we give them type O blood. Nothing will happen. And so we like to think of AB as the universal

recipient. In other words, it can get blood from any other type and it's going to be fine.

But if we look at type O blood. Type O blood since it has the other antibodies. If we throw

anything with a protein, especially like AB blood you can wee that all the antibodies

are going to grab on to that. And so it's really important when we're giving blood from

one person to another that we match that blood. Now if you're trying to solve genetics problems

using blood, you simply have to memorize this. Because it's really hard to just answer questions

dealing with blood type unless you understand the genetics behind it. And it's not simple

Mendelian genetics. So basically there are four different phenotypes. So you could be

type A, B, AB or O. But there are six different genotypes. And so if you're type A, like I

am, you could be A because your have both of these alleles for A or your homozygous.

Or you could be heterozygous. You could have one of the alleles for the A protein but the

other one doesn't make a protein at all. That's how you get the type O. If you have two alleles

and neither of those express the protein. If you're type B, again you could be homozygous

for both of those or you could be heterozygous. But if you're type AB blood then you're going

to have to have one of each. And so we call this expression, well multiple alleles because

we have more than one allele, we have three in this case. And also it's codominate. Because

if you're type A and B, you don't have like one being dominant. You're actually expressing

both of those. And so if you're ever trying to solve problems, they're never going to

give you this genotype. So you really have to memorize this. I or the AP folks are just

going to simply ask you a question like this. Is it conceivable that we could have a father

who is type A and a mother who is type O. And they could have offspring that are going

to be type B, we'll say for an example. Well to solve this let's look at a couple of punnett

squares. If you're type A, we just write that across the top. So you could be this. You

could be homozygous for that A. We know that the O is going to look like this. And so we

could figure out that all of the offspring, if the parent is homozygous is going to be

type A. But if we kind of delete that a second. Let's say that they are heterozygous for it.

Let's say that person whose type A is going to be like that. And then O looks like this.

Well we could get this possibility. This person would be type A blood. But we could also get

this possibility. With this one being type O blood. Or you could solve questions like

this. Let's say that we have one parent who is A and one parents who is B. What possibilities

could we have for their offspring? Well, let's look. If one is A and one is B, if they're

both homozygous then we would have AB blood for all of their offspring. But let's set

it up another way. Let's set it up like this. Let's say that one is heterozygous for it,

like that. And then the other is heterozygous for that trait. So let's say dad is B but

he's heterozygous for that trait. Well, if we look at this possibility in fertilization

this person would be type AB blood. This person right here is going to get the A from up here

and the i from over here. So this would be type A blood. This one right here would be

B blood. And then this one right here, since you're getting both of these little i's is

going to be type O. So if you have an A and a B you conceivably could get AB, B, A or

O type blood coming from that. And so make sure you understand the different genotypes

that we have. Especially up here for those who are type A and type B. Next thing I want

to talk about is quickly the Rh factor. Rh is simply another set of proteins. This is

a little simpler to do genetics problems with Rh factor, because you either have it or you

don't. Either you're Rh positive, and you have these Rh factors. Rh came from, they

did some early studies on the rhesus monkey to identify this protein. Rh negative you

don't have it. And so what antibodies does an Rh+ going to have? Well neither. It's going

to have none of those antibodies. But if you're Rh-, then you're going to have those Rh+ antibodies.

And so the genetics are pretty simple. If you're Rh+ you could be either homozygous

or you could be heterozygous. If you're Rh- then you're going to be homozygous negative.

So which is dominant? Dominant is going to be the Rh+. And so if we have a parent, two

parents who are Rh+, is it conceivable that they could have offspring who are Rh-? For

sure. If they're both heterozygous we could just go like this. These would be the offspring.

This one would be Rh+, Rh+, Rh+ and this could be a Rh-. And so the genetics are pretty simple

but there's something you really want to be aware of. Now, if we've got a mom right here.

And let's say she's Rh-. And then we have a dad who is Rh+, is it conceivable that they

could have an offspring who ends up being Rh+? Well for sure. And so basically what

happens is during the first pregnancy, nothing really happens. Because we're only sending

antibodies in one direction. From mom to baby. But during child birth, there's a lot of blood

that gets mixed. And so basically what can happen is during subsequent pregnancies, now

mom is going to start building up a lot of these Rh+ antibodies. And so during the second

pregnancy she could actually be sending antibodies that could damage that fetus. Now if we know

this, which we do in developed countries, then we can simply give her a chemical during

I think the 28th week of gestation and then we can suppress that immune response. But

it's really important that we know that. And so now we finally get to this last big chart.

And it's got some really cool information on it. If you look here it's got the donor

and the type of blood they have. And then the recipients and whether or not you could

get it or you couldn't. And so if we look at somebody right here, let's say we're giving

O minus or O- blood, well we could give that to all these people. From O all the way to

AB. And so that's why we call that O- the universal donor. And then if we look down

here at AB +, well AB+ could get blood from all of these different types. And so we call

them like the universal recipient. And so who would they love to see as far as donating

blood? It's going to be somebody who's O-. And what percent of the population is that?

6.6%. And so if we look at some of these percentages, what's the most common? The most common is

going to O+. Almost 38% of the population is going to have that. Same with A+. And then

we're going to have some more obscure blood types like AB- where it's less than 1% of

the population that has that. But there's something unique. If you look at some native

population, like native Australian Aborigines, we find that B really didn't exist before

Europeans showed up. And the same thing in Native Americans. And so we can look at these

proteins, that really don't have a function, or maybe they have a function that's lost.

And we can kind of trace human ancestry. So that's blood typing. It's important when we

switch blood or when we're trying to solve some genetics problems. And so I hope that's

helpful.