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Archiver > SOUTH-AFRICA > 1998-12 > 0912941560


From: MICHAEL O'CONNOR<michael.o' >
Subject: Re: Blood Types
Date: Sun, 6 Dec 1998 12:52:40 +0200 (GMT)


Mike,
You are looking at 2 (the ABO and the Rh) of the many blood grouping
systems. they have other names but this is just to simplify for you.
In the ABO system there are 4 possible blood groups A, B, AB and O. Now the
first 2 can be homozygous or heterozygous (forget about the big words) which
means that they can be either AA or AO or BB and BO. Now if one of these was
a male and fathered a child the following possible "sperm" could be the ones
that fertilise the ovum
A or A from the AA, A or O from the AO, B or B from the BB and B or O from
the BO.
Of course if the man is of the AB blood group then his sperm would either be
A or B.
Put in a table form with the male sperm on the top line and the female ovum
on the upright these are all the possible blood groups from each mating

AA AO BB BO AB
______ _______ _______ ________ ________
A A A O B B B O A B

! A AA AA AA AO AB AB AB AO AA AB
AA !
! A AA AA AA AO AB AB AB AO AA AB

! A AA AA AA AO AB AB AB AO AA AB
AO !
! O AO AO AO OO BO BO BO OO AO BO

! B AB AB AB BO BB BB BB BO AB BB
BB !
! B AB AB AB BO BB BB BB BO AB BB

! B AB AB AB BO BB BB BB BO AB BB
BO !
! O AO AO AO OO BO BO BO OO AO BO

! A AA AA AA AO AB AB AB AO AA AB
AB !
! B AB AB AB BO BB BB BB BO AB BB

A person who is AA or AO will be blood group A
A person who is BB or BO will be blood group B
A person who is AB will be blood group AB
A person who is OO will be blood group O
Similarly
A person who is ++ will be Rh+ve
A person who is +- will be Rh+ve
A person who is -- will be Rh-ve

You can construct charts for just the Rh as well as combined charts with the
ABO and Rh to get various combinations. From the charts you can work out
what possible blood groups any progeny resulting from a particular mating
would be. You will immediately see that it is impossible for a person who is
blood group AB to have a natural child who is blood group O.
Please note that this is just simplified to explain it Mike so if there are
more enlightened people out there who would like to correct me please feel free.
Regards
Mike

Michael O'Connor
Orchid Grower and Genealogist
Researching the names O'Connor/Connor/Connors
Pietermaritzburg
South Africa

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