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Does anyone know anything about blood groups?

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ProfilePosted byOptionsPost Date

Lee in Yorkshire

Lee in Yorkshire Report 24 Jun 2008 15:57

If I am O Rhesus positive, does one of my parents have to have the same blood group?

Lee x


SheilaWestWilts Report 24 Jun 2008 16:02

Lee - I don't think so, you could be an O child with 2xA, or 2xB parents. However, neither parent could be AB.

Lee in Yorkshire

Lee in Yorkshire Report 24 Jun 2008 16:04

Hi Sheila

What if one parent is A and the other B?

☺Carol in Dulwich☺

☺Carol in Dulwich☺ Report 24 Jun 2008 16:05

Regarding the rhesus positive/negative blood type, two rhesus negative parents will always get rhesus negative children, but two rhesus positive parents can get both rhesus positive and rhesus negative children.


SheilaWestWilts Report 24 Jun 2008 16:05

Yes, O is possible there,too!

Lee in Yorkshire

Lee in Yorkshire Report 24 Jun 2008 16:11

Thanks for the info everyone xx


MrDaff Report 24 Jun 2008 16:17

I am O neg, hubby A pos... both of my sons have pos blood groups.

My mother is AB neg, my father O pos.

My in-laws were both pos.

Both of my granddaughters have positive blood groups.

My parents had 9 children, I am the eldest. Only three of us had negative blood groups!!


Daff xxxx


Kay???? Report 24 Jun 2008 16:38

O can donate to any blood group..but can only recive O in return,

O is the most common in the world,#

I'm O- RhD positive,,


MrDaff Report 24 Jun 2008 16:43

lol Kay!!

As an O neg... I can give to almost anyone, but can only have O neg (not even O positive can touch my delicate little veins, lol) , which makes me one of the rarest receivers in an emergency. They took my own blood from me and stored it whenever I was in a position of maybe needing it, in the past. I was also on the Military Emergency donor list for years, until I started my BP tablets.


Daff xxx


Kate Report 24 Jun 2008 16:43

Sounds like I must have really common blood, too, Kay - I'm O positive as well. (I'm sure I read somewhere - don't know if it's correct or not - that before the Normans/Vikings/Saxons etc invaded Britain, every one of the ancient British people here had type O blood, so that must mean I have a long line of very British ancestors to locate!)

♥ Kitty the Rubbish Cook ♥

♥ Kitty the Rubbish Cook ♥ Report 24 Jun 2008 16:44

I am B neg anti d.............whatever that means, my husband is O positive.

Children are O neg.,O positive and B positive.


♥♥♥Debbie♥♥♥ Report 24 Jun 2008 16:46

Me and my sister have different blood groups and we have the same mum and dad, i know that wasn't the question but i thought we would be the same. Debbie

Helen in Kent

Helen in Kent Report 24 Jun 2008 16:56

Further to a previous reply, my mother was o negative, my father o positive and my brother and I are both o negative.

My children, with an o positive father, are all o positive themselves.

Anti D is, I think, what you are given as an O negative mum after giving birth to an o positve baby, to make sure baby's antibodies don't start killing off your blood. I had a lot of it, with 3 o positive children!

A neighbour of mine had anti D in her blood and used to be escorted to give blood as if she was the queen.


Kay???? Report 24 Jun 2008 17:04

Daff,my sister & brothers are O neg,,,with the same problem,,

O is the most requested when transusion is needed,,


MrDaff Report 24 Jun 2008 17:14

Helen... I had the anti D jab after my two babies, and after my miscarriage.... and yep, I was treated rather like Royalty, lol!!

Kay, my GP even weaned me off my BP tablets (I was on a very low dose at the time) for a few months, under very strict supervision and at my own request, leading up to the 1st Gulf War, in case it was required. I was given a pager... not that I would have known how to use it, lol!!


Daff xxx

(¯`*•.¸*Karen on the Coast*(¯`*•.¸

(¯`*•.¸*Karen on the Coast*(¯`*•.¸ Report 24 Jun 2008 17:16

very confusing to me......

does anyone know what a rare group would mum said her mum had a rare blood group and had to carry a green card around with her,

Karen x


Kay???? Report 24 Jun 2008 17:18

they carry a card at all times with their blood details on,or did do,,,

Lee in Yorkshire

Lee in Yorkshire Report 24 Jun 2008 17:21 and me both Karen

Im still trying to work it all out.


Danielle-Marie Report 24 Jun 2008 17:45


Just for anyone that is interested. O is a recessive gene whilst A and B are equally dominant. This means that a person who is classified as A +/- may have AO genes or AA genes.

Someone classified as B may have BO genes or BB genes

Someone with O however must have OO genes

A child therefore with two O blood group parents must have O blood because these are the only genes that can be passed on.

A child with two A parents could have A blood or O blood depending on the wether the parents had AA or AO blood.

AB is the rarest blood group
B is the nest rarest
A the next
O the most common

And negative is more rare than positive.

AB can recieve AB blood A blood and B blood (and poss O)
B can receive O and B
A can recieve O and A
O can only receive O

Negative is also recessive meaning they must have - - genes (hence why two negative parents can only have a negative child)

Hope this helps
Please let me know if it does (or if I've got something wrong)

Danielle xx

Sue in Somerset

Sue in Somerset Report 24 Jun 2008 18:19

I'm AB positive.

I tried being a blood donor but have a circulation problem which meant they can't get blood easily. I was disappointed that I'm not allowed to donate but it was explained that my blood group would only be given to tiny babies whose immune system isn't so sensitive. Otherwise it can only be given to exact matches which are rare.

My husband is O positive and so we knew our kids would get one of his two O genes. (he'd actually be OO positive but we don't call it that).
The kids then had a 50% chance of getting either my A or my B.

In fact they are both B (which means they are actually OB).
Having a B or A means their O is hidden but their own children have a 50% chance of inheriting either a B or an O gene from them.

We could have ended up with everyone in the family with a different group if one of my girls had been an A instead of a B.

For me to be an AB one of my parents must have had an A and the other a B but one of them could have been actually AA or AO or AB while the other a BB or OB or AB...........bearing in mind we don't usually use both letters unless it's AB.

I had this explained to me by my daughter when she was doing her A level biology.