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From the “ABCs of Family Research,” we have this discussion about Blood Types

There is another aspect of learning about your genealogical background that is sometimes ignored, or at least not emphasized enough, in my opinion, and that is researching your blood type and the blood types of your family members.

How important is blood type in doing family research?  The answer to that question depends on how much you want to know about yourself and your family, and in some respects it also depends on how you view the origin of life on earth.  Certainly traditional family research does not usually address the ancestor’s blood type, but, let’s face it, depending on where you come from geographically, you will have certain body styles, certain facial features, certain mental styles, etc.  Are those characteristics caused by, or identified by knowing ones blood type?  Perhaps.

Some of us believe that all life on Earth was created by a personal God, and so we are all simply human beings, or cats, or dogs, etc. in His eyes.  Maybe all of that is true enough.

Others among us believe that the Earth is a giant experimental petri dish, with life planted here by celestial aliens as part of their grand experiments.  Or, did those same celestial aliens plant us here to farm us for our productivity?

And still others among us are Deists who do not have a personal god, and have no specific idea of what it is all about or where we came from.  It’s just a big mystery.

One thing about human history that seems apparent is that there have been different ages of humanoids, and that our history has been fogged over or eradicated enough so that we don’t have a clear picture of human history on Earth.

Domestic Animal Blood Types

We are humans, but it seems that every animal life form on Earth has one or more different blood type in their species.  Crazy, huh?

For example, domestic cats have what is called the AB blood type system. The most common blood types in cats are type A and type B.  Cats with blood type A have naturally occurring anti-B antibodies, and cats with blood type B have naturally occurring anti-A antibodies. There is also a third and less common blood type in domestic cats known as type “AB.”  Cats with the less common “AB” blood type are thought of as the universal recipients.

Domestic dogs, on the other hand, have more than 12 blood types, and their red blood cells may contain any combination of these since each blood group is inherited independently.

Knowing blood types in domestic animals like dogs and cats, is often important because of the need for a blood transfusion caused by an emergency, such as severe bleeding, the sudden destruction of red blood cells due to some disease, or maybe to treat anemia.  This is true for humans also.

Human Blood Types

Now we get into our own human species and its blood types.  Not wanting to get too technical on this subject, in humans there are eight generic blood types, including type A, type B, type AB, and type O and, and each of these four basic blood types has its own Rh positive or Rh negative variation.

The Rh designation (sometimes called ‘Rh factor,’ ‘rhesus factor,’ ‘factor’ or ‘protein’) is named for the rhesus monkey, which also carries the same gene, and is a protein that lives on the surface of some people’s red blood cells.  A person with O Rh positive (or simply O+) blood type has this rhesus monkey gene, and a person with O Rh negative (O-) blood type does not.

In the United States, approximately 85% of the population has an Rh positive blood type, and about 15% have Rh negative.  And just as we inherit our generic blood type (A, B, AB, and O) from our parents, we also inherit the Rh factor from them as well.

But now, and thinking philosophically, comes the tricky part.  Those with Rh positive blood types are shown to be related to other animal life forms on Earth.  Those with Rh negative blood types appear to NOT be related to any other animal life forms on Earth.  So we are all one human race, eh?  Really?  Where did the Rh negatives come from?

Similar to other animal blood types, humans try to maintain consistency with regard to blood types when it comes to blood transfusions as this next chart (Red Blood Cell Compatibility Chart) shows us.  In the chart, you will note that the blood type O- is the universal blood donor type, that is, any human can accept O- blood type in a transfusion.  But it doesn’t work the other way around.  Anyone who has Rh positive blood type can receive blood from someone who is Rh negative, but those with Rh negative blood types cannot receive blood from those with an Rh positive blood type.

Blood Cell Compatibility Chart

Reviewing this chart, and thinking about blood transfusions for ourselves and for our family, this should be telling us that knowing our own blood type is important.  But, unless you have donated blood at the Red Cross, or have had other medical reasons for specifically knowing your own blood type, chances are that you probably don’t know it.

How important is knowing your own blood type in 2018?  Well, if you are in an accident, and you get taken to a fairly good sized hospital, the ER nurse will determine your blood type before he/she gives you blood, or, alternatively, he/she will often give you type O- blood.

I asked a family physician once what his blood type was (he looked like an Rh negative) and he said he had no idea.  I asked him ‘Really?’  His response was that hospitals now check blood types of patients as a matter of course.  I suspect that he just didn’t want to tell me his blood type.  Why?  There seems to be some covert conspiracy that intends to keep us from knowing our own blood types.  Why?  I have no idea why.

So, how does one learn their blood type?  There appear to be four primary methods of learning your blood type.  You can join the military, you can donate blood, you can ask your doctor to run a blood type test for you, or you can buy a home blood test kit.

If you don’t want to join the military, visit your doctor, or donate blood, you can find a home blood type test kit online or at a pharmacy for the cost of about $10 USD.

In the twentieth century, blood tests were used for paternity testing, but in 2018 blood type is probably no longer used.  DNA testing is now used to resolve paternity questions.  The child’s DNA is tested and determined and the alleged father’s DNA is determined, and if there is one or more DNA markers that line up, the man is shown to be the father.  The same can be said for evidence of the mother’s connection.

Notice that most commercial DNA testing typically focuses on DNA markers, not on blood type, so when, and if, you choose to have ancestral DNA testing done for yourself of other members of your family, you may or may not receive estimations of your blood type.  The commercial DNA testing services do not appear to specifically post your blood type as one of their test results.  I also suspect that forensic DNA testing labs no longer include blood type in their DNA test results.

Rh Negative Blood Types

So, why all of the discussion about blood types if no one uses blood types for identifying people anymore?  The answer is because the Rh negatives are an integral part of human history and because they have certain identifiable traits and characteristics that are, or may be, important parts of our own history.

As a family researcher and historian, you are part of the history profession, whether you think so or not.  In your own research of history, everything you discover counts.  If knowing your own blood type helps you find and identify your ancestors, then good for you.

So what, you ask.  Aside from not being DNA connected to any other earthly life form, what makes Rh negatives special?  Only deeper research can provide that answer.



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