I am and O blood type...... does that mean both my mother and father have to be an O?  Or can a type O and type A have and O child?
I am thinking that in order to be a blood type O that both mother and father had to be type O.
And that a blood type O and blood type A can not have an O child.

O and A parents can have group O offspring as long as the A parent is heterozygous, ie has an AO genotype rather than homzygous AA.

My mother is an A, my father is an O, my brother is an A and I am an O.

Ee-I-Ee-I-O  

My mother is an O, my father is an A, and my sister couldn't bring herself to do the test I sent her.  She could be A or O.

Oh yeah, O's and A's make terrific kids. Both of ours are O's.

Anyone, except an AB, can have an O child...unless they know that they're homozygous AA or BB, but most people don't have or need that information.

I'm and O, my husband is an A, and our kids are one O and one A.  My husband's parents are O and A, also, so we know my husband is heterozygous, Ao, as is our type A son. (I also owe his recessive O gene for our other son being an O.)

I'm an A, my husband is an B and my sons are O and B.

I'm an AB, my dad is an A and my mother is a B with my siblings being A, B, and O. No, I am not joking, had BTD been around when we were kids my mom would've been stuck with taking care of all 4 types. This also means that my dad has to be AO and my mom has to be BO. If this where not so, they could not have had one of my brothers who is an O because O's are always OO because it's the recessive trait.

Yes, you can come help me do our cooking for family get togethers!

My husband is an O. We have an A son. So he's got to be an AO rather than an AA since he is half of my husband's OO and got the A half of my AB.

maybe your mom s an Ao and the 'milkman' is the O in the equation!

Lola, all cases above can produce an O child...which one are you talking about?  

sorry, I meant Chanur s case.....
Bo...my bad!!
but the milkman is probably still the O.....
bad joke, I know!

Quoted from Chanur

I'm an AB, my dad is an A and my mother is a B with my siblings being A, B, and O. No, I am not joking, had BTD been around when we were kids my mom would've been stuck with taking care of all 4 types.

That's my husband's family exactly!  His dad's a B, his mom's an A, and they have 4 children--one of each type.  His mom says, "Boy, I wouldn't have ever followed that diet."

I am an O and my hubby is an A and we have two daughters...one O and one A.

Debra

Oh, wouldn't it be so simple just to have all Os?  We have at least three different types so far in our family.  And now with me switching to the GTD, we're really 4 different types.  Maybe I'll switch my A son to my diet, but there's such huge differences in the A diet and the Warrior diet, I don't know what to think.

My dad's an O and my mom's an A - the 5 of us kids are a combination of Os and As.  

My father is an O, my mother is a B.  They had four of us girls all togther.  Three of us are O's and one is a B.
I married an A.  Our first three children are O's and our 4th is an A.  I'm still waiting on baby #5 to know what he/she is.
When my husband was in his biology class in college a few years ago the teacher told him that our first three children weren't his!  She said that it was impossible for anyone who was an A to produce an O heir.  
I'm glad I wasn't there to hear that!  It kills me how some people want to put science in a box.  Have some creativity, for crying-out-loud!

Leanne!

great teacher he had there!

That teacher knew nothing, since ABO bloodtypes are some of the most basic science.

Here's how it works.  In our bloodtype there are 3 letters: A, B, and O (I know, it's not really "letters", but I'm keeping it simple).  Everyone gets 2 of these letters to make their bloodtype.  A and B are always expressed, but O is not.  Think of O as "zero".

So, you can be the following:

AA or AO = Type A bloodtype
BB or BO = Type B bloodtype
AB = AB bloodtype
OO = O bloodtype

Notice that AB and O bloodtypes have only ONE WAY for them to be that bloodtype, whereas A bloodtype and B bloodtype have TWO ways to be that bloodtype.

OK.

When 2 people get together to have a baby, EACH one of them contributes ONE of their own bloodtype letters to make the baby.  Remember, they have TWO letters, but they give ONE only to the baby.

So the following can happen:

If you are bloodtype AA, which is the A Bloodtype, you will ONLY contribute an A to the baby.

If you are bloodtype AO, which is also the A bloodtype, you can give the baby EITHER an A letter OR and O letter.

If you are bloodtype BB, which is the B bloodtype, you can give the baby ONLY a B letter.

If you are bloodtype BO, which is also the B bloodtype, you can give the baby EITHER a B letter OR an O letter.

If you are bloodtype AB, which is the only form of the AB bloodtype, you can give the baby EITHER an A letter OR a B letter.

If you are bloodtype OO, which is the ONLY form of the O bloodtype, you can ONLY give the baby the letter O.

SO

you can see how two people with bloodtype A could produce a baby with bloodtype O.  In that case, BOTH parents would have to be the AO bloodtype AND the bloodtype of the baby could be either AA, AO, or OO.  Overall, that baby would have a 75% chance of being an A bloodtype.

Your typical test for determining bloodtype does not tell you which two letters you have.  You are told you are "Type A", but you don't know if you are an AA or an AO.  You can most easily figure this out if you know your parent's bloodtype, your children's bloodtype and your mates bloodtype.  If all the adults are type A, but an O child pops out here and there, you know that someone in the family is an AO type A.

I hope that this is clear.

BTW, the only combo that most certainly CANNOT result in a type O child is if BOTH parents are AB.

My understanding is that O is an A mutation, so of course an A can have an O!

Quoted from AnutLisa

My dad's an O and my mom's an A - the 5 of us kids are a combination of Os and As.  

So, you know for a FACT that your mom AO.  If she weren't, there could be NO Type O children!  She is the one that has to contribute the other O to her Type O offspring!

This stuff that was discussed was learned in freshman biology class.  How terrible to tell someone his kids weren't his.

I met someone whose parents were A & B & had an O sibling, as well as other types. I think that is the coolest combination - to be able to produce all types.

My husband & I are the reverse - he's an AB & I'm an O with an A child & B child. That also is a cool combination.

My parents were A & O and my sis & I are both Os. I was disappointed to be an O, but now am glad. (I guess I don't like the letter O. Maybe we should be called Omega with the Greek letter. Now that would look very classy!)

I really don't mind having all types. Of course my kids are grown, so I don't feed them often.  I liked to cook & s tayed home, so if I had to do it, I'm sure I could work something out. There are plenty of compliant for all foods, especially veggies. Many folks who don't do the BTD have limited diets, anyway. Most families have certain eating patterns & eat little variety. For some, the BTD is an expansion of diet.
S S & L,
Mrs "T"    O+

I have to be a BO because my A husband and I have an A daughter, but still don't know if he's AA or AO. Maybe this next baby will shed some light.

My mother's an A, my Dad was an O.  Both my brother and I are Os.  He's O+ and I'm O neg.  My ex is an AB and both our kids are A+.  I know that for sure because I had to have a rhogam shot after each delivery.  Whoever that teacher was should be ashamed...basic Mendelian biology.
Jane

OK, I have a senario and I want to know if it's possible.
Parents of father:
Dad - B
Mom - A
Parents of mother:
Dad - O
Mom - B

The parents:
Mother - O
Father - B

Here are their childern's blood types:
#1 child - B
#2 child - O
#3 child - A

Now, is that last A child possible or was their hanky-panky going on?  The only A factor in all of this is the mother of the father.  Could he be a BA and have passed that A on to his child?
Very curious about this!

Leanne!

Quoted from Leanne

Now, is that last A child possible or was their hanky-panky going on?  
Leanne!

How about an adoption?