Topic
l am an AB+ which I've been told is one of the more rare blood types....can someone explain in laymans terms why some blood types are so common and others are not.....
Why are some blood types so much more rare then others
AB is rare mainly because B is rare. And then u have to apply normal gene rules to inheritence.
B group originated in asia & in the west only around 10% of people have B.
You then have the probability of meeting someone with an A blood group (about 40-45% of the population).
Then u have the probability of having an AB child.
Giving around 3-5% of the population overall.
Rhesus positive is actually more common than negative (ignore other on this) about 75% to 25%. And the inheritence is pretty straight forward (actually complex but appears to follow simple rules). The problems in childbirth mentioned only apply if u Mother is Rh negative & this does not effect the blood group u have it just can cause complications at birth (my mum had this actually she had to be carefully monitored when my younger sister was born)
http://en.wikipedia.org/wiki/Blood_groups
PS u r a universal recipient which means u can have any blood type in a transfusion.
Why are some blood types so much more rare then others
To address this in a more simplistic manner we will talk about inheritance. This question can be compared to why there r so few redheads. The genes that give u ur hair color or blood type r inherited from ur parents. 1/2 from mom & 1/2 from dad. However, some genes r less potent in a way like the gene for red hair & other more dominant traits will most likely override the less dominant trait. If ur mother has red hair & ur father has brown hair u r much more likely to have brown hair. The same goes with brown eyes & blue eyes. If ur father has blue eyes & ur mother has brown there is about a 1/3 chance u will have blue eyes in comparison to the 2/3 u will have brown. This is basically the same for blood types. However, u can have two brown haired parents have a red headed child because of the less dominant genes. These ''recessive'' genes can show up farther down ur family line. So if u have blood type AB+ someone in ur family at some time had that same blood type as well & it has just now resurfaced in you.
Why are some blood types so much more rare then others
When u do a pedigree, u will be a 1/4 combination of ur parents' blood types-that is not the rarity. The deal with u is u r positive for the Rh factor. Your mother could have created antibodies for ur blood type & could have had, to say the least, some complications or even a miscarriage. The rarity comes from the probability of getting the Rh factor, which is a linked gene on a chromosome & has a lot of antigens.
Sorry I could not simplify this any more.