The Sound of Science - 'Rh Factor'
Becky: You're listening to The Science of Science on WNIJ. I'm Becky with NIU STEAM.
Newt: And I'm Newt. If you caught our last episode, you'll know we're talking about blood. We learned that types A, B, AB, and O are the result of sugar based antigens. So in this episode, we're going to look at how we determine whether our blood is positive or negative. This part of blood typing is based on the presence of the Rhesus Factor usually just called Rh. Both parts of blood typing are found on the red blood cells membrane, but unlike the sugary antigens from before, this antigen is based on a protein.
Becky: If you have positive blood typing, the Rh protein is present. If you have negative, the Rh protein is not. All blood typing is important in transfusions, but Rh typing also impacts pregnancy. The first time an Rh negative person is pregnant with an Rh positive baby, that person creates antibodies against the Rh protein. The Rh positive baby is usually born okay.
Newt: However, if that person gets pregnant again, with an Rh positive baby, there's a risk of complications. The fetus might suffer from hemolytic anemia, which means its red blood cells are destroyed faster than they are replaced. This can result in health problems for the baby, including stillbirth.
Becky: To avoid this, the pregnant person needs to be given specific treatment before their body creates the antibodies. This treatment suppresses the creation of antibodies during the first pregnancy, which makes a second pregnancy much safer.
Newt: You might be wondering what the purpose of these antigens is. I was very curious when I first learned about this. Well, we apparently don't know yet. Some suggest that these antigens are vestigial that they used to have some purpose, but no longer serve a function. The reason we think they're useless right now is that people without one or all of these antigens suffer no ill effects.
Becky: Like all of science, this is based on what we've noticed so far. That doesn't mean we won't figure more out eventually, just that the evidence has not been observed yet. Who knows what we will notice next. This has been The Sound of Science on WNIJ, where you learn something new every day.