YOUR RHESUS FACTOR, BLOOD TYPE AND GENOTYPE

RHESUS FACTOR

Rhesus (Rh) factor is an inherited protein found on the surface of red blood cells. We can either be –

Rh positive means that your red blood cells have the protein while Rh negative means you lack the protein.

 

Most people are Rh positive. Being Rh negative doesn’t affect your health in any way except during pregnancy. This brings us to the importance of knowing your  Rh factor.

 

If a mother that is Rh negative has a child with a man that is Rh positive, there is a possibility that their first child will inherit the Rh factor from the father. The baby will be Rh positive while the mother is Rh negative. This is known as Rh incompatibility. This can be lead to the death of the second baby if he/she also inherits the Rh factor from the father. The reason for this is that, during delivery, it is possible for a small amount of the baby’s blood (Rh positive) to come in contact with that of the mother (Rh negative).

 

The baby will survive and be okay but the mother’s blood will produce Rh antibodies to protect the mother against Rh-positive blood. The body of the mother, Rh negative sees the Rh-positive blood of the baby as a threat so it produces antibodies to protect the mother against any future threat. So, if the second baby is also Rh positive, the antibodies will cross the placenta and cause damage to the baby’s red blood cells and this can lead to haemolytic anaemia and erythroblastosis fetalis.

 

To avoid this, you can either get married to someone who has the same Rh factor as yours or receive an injection of RhoGAM (Rh immunoglobulin) during your pregnancy and immediately after delivery. This injection prevents your body from producing Rh antibodies during your pregnancy. If your baby is Rh negative and you are Rh positive, no treatment is needed. But if your baby is Rh positive and you are Rh negative, you will be given RhoGAM during your first trimester and immediately after delivery.

Other situations in which your healthcare provider can give RhoGAM injection to you include:

 

BLOOD GROUP

There are four main blood groups. They are

Blood group O is the most common blood group.

Each blood group can either be Rh positive or negative. It means that there are eight blood groups in total. They are:

O+ blood group is the most common type of blood group.

O- is a universal donor which means they can donate to all other blood groups..

A person with Rh- blood can donate to a person with Rh- or Rh+ while a person with Rh+ blood can only donate to a person with Rh+ blood.

 

BLOOD GROUP	DONATE TO	RECEIVE FROM
A+	A+ AB+	A+ A- O+ O-
A-	A+ A- AB+ AB-	A- O-
B+	B+ AB+	B+ B- O+ O-
B-	B+ B- AB+ AB-	B- O-
O+	O+ A+ B+ AB+	O+ O-
O-	A+ A- B+ B- O+ O- AB+ AB-	O-
AB+	AB+	A+ A- B+ B- O+ O- AB+ AB-
AB-	AB+ AB-	AB- A- B- O-

 

GENOTYPE

Genotype is the genetic constitution of a person. Most commonly, in this part of the world we use the term genotype as it relates to sickle cell disease. It is very important to know your genotype and that of your partner before deciding to have children.

We have various types of genotype, they include:

GENOTYPE COMPATIBILITY

A man and woman are said to be compatible when they have no possibility of giving birth to a child with the sickle cell disease which is a very serious illness.

PARENTS’ GENOTYPE.	CHIDREN’S GENOTYPE	COMPATIBILITY
AA + AA	AA, AA, AA, AA	COMPATIBLE
AA + AS	AA, AS, AA, AS	COMPATIBLE
AA + AC	AA, AC, AA, AC	COMPATIBLE
AA + SC	AS, AC, AS, AC	COMPATIBLE
AA + SS	AS, AS, AS, AS	COMPATIBLE
AA + CC	AC, AC, AC, AC	COMPATIBLE
AS + AS	AA, AS, AS, SS	INCOMPATIBLE
AS + AC	AA, AC, AS,SC	INCOMPATIBLE
AS + SC	AS, AC, SS,SC	INCOMPATIBLE
AS + SS	AS, AS, SS, SS	INCOMPATIBLE
AS + CC	AC, AC, SC, SC	INCOMPATIBLE
AC + AC	AA, AC, AC, CC	INCOMPATIBLE
AC + SC	AS, AC, SC, CC	INCOMPATIBLE
AC + SS	AS, AS, SC, SC	INCOMPATIBLE
AC + CC	AC, AC, CC, CC	INCOMPATIBLE
SC + SC	SS, SC, SC, CC	INCOMPATIBLE
SC + SS	SS, SS, SC, SC	INCOMPATIBLE
SC + CC	SC, SC, CC, CC	INCOMPATIBLE
SS + SS	SS, SS, SS, SS	INCOMPATIBLE
SS + CC	SC, SC, SC, SC	INCOMPATIBLE
CC + CC	CC, CC, CC, CC	INCOMPATIBLE