Genotype is the genetic makeup of an
individual with reference to a trait or
multiple traits. They are the collection of
genes passed from parents to the children.
Alleles or Allelomorphs are also referred to
as the genes. Children born of a parent will
have different genotype. Exceptions are
seen in cases of twins or multiple births
that are fertilized from the same egg.
Human beings have two alleles with each
pair inherited from each parent. An allele
represents a gene.

Before the advent of modern medicine ( read
about how modern medicine came to
Nigeria here), there was high mortality and
infant death rates. All these children lost to
the cold hands of death were referred to as
"abikus". All these happened because there
was no knowledge on blood group or
genotype. People that get married
irrespective of their genetic makeup should
not be blamed for their ignorance. But with
the advent of modern medicine( read about
modern medicine and its advantages in
Nigeria ), biological explanations are now
being made on the causes of infant death
rate, this led to the discovery of sickle cells
in Africa, especially in Nigeria. Before
marriage, partners should be aware of their
genotypes and blood group as the society
no long provides excuse for this ignorance
( read an interesting article named no
excuse for ignorance here). Parents should
check the genotype of their children during
pregnancy or immediately after birth. This
will help to know the health status of the
child and what they have to do to sustain
and maintain the child's health.

There are four genotypes in humans - AA,
AS, SS and AC. AC genotype is not so
common and popular unlike the other
three. SS and AC are the abnormal
genotypes or the sickle cells. The
knowledge of genotype is important when
choosing life partners. Intending couples
should know both their own genotype as
well as their partner's genotype at the early
stage of their relationship before they are
well rooted in love and emotions. Emotions
and time spent in the relationship can cloud
people’s judgment or decision to break up
if they are not compatible, thus, giving birth
to sickle cell children and subjecting
themselves and their children to pain,
torture and agony.


Possible Outcomes of Different Genetic
Combination
AA + AA = AA, AA, AA, AA
AA + AS = AA, AS, AA, AS
AA + SS = AS, AS, AS, AS
AA + AC = AA, AA, AA, AC
AS + AS = AA, AS, AS, SS
AS + SS = AS, SS, SS, SS
AS + AC = AA, AC, AS,SS
SS + SS = SS, SS, SS, SS
AC + SS = AS, AS, SS, SS
AC + AC = AA, AC, AC, SS

People with the genotype AA are prone to
malaria sickness at their early ages. Sickle
cell arises when there is any blockage in the
blood vessels which inhibits the flow of
oxygen. When the red blood cell do not
have the required oxygen, there will be
changes in its original shape (disc shape)
to a "Sickle-like" or "crescent-like shape" ,
Thus, the name "sickle cell". Sickle cell
patients experience severe pains in body
parts that lack oxygen flow. Their bone
marrows will fail to produce red blood cells
and this result to anemia. To save this
crisis, blood is usually transfused to them.
In terms of compatibility, someone with AA
genotype can marry anybody. It is safe for
someone with AS to marry someone with
AA genotype. The combinations of AS and
AS, AS and AC should not be risked. There
is probability of having a SS. Although. Two
sickle cells should not even have a
relationship or get married. Individuals with
the AA genotype should help you prevent
genetic abnormalities by marrying the AS,
AC and SS. By this, we are hopeful to
eradicate sickle cells in the world.

Blood Groups / Blood Types
The red blood cells that transport oxygen in
the body carry two antigens, which are the
A and B antigens. These antigens
determine the blood group. Blood groups
are represented with A, AB, O, and B. When
the red blood cell carries only the A
antigen, the blood group is 'A', it is 'B' when
the blood cell has only the B antigen. When
both A and B antigens are present, the
blood group is 'AB'. Finally, when there is
neither A nor B antigen, the blood group is
referred to as ’O’.

Below is the cross breed of different blood
groups and the products (offsprings)
A + A = A or O
B + B = B or O
A + B = A, B, AB or O
A + O = A or O
B + O = B or O
A + AB = A, B or AB
O + O = O only

The genotype of blood type A is AA or AO.
The antigens on the blood cell are A and
antibodies on the blood plasma are B.
For blood type B, the genotype is BB or BO
with A as the antigens and B as antibodies.
The blood type AB has the genotype to be
AB. The antigens are both A & B, and no
antibodies on the blood plasma.
The blood type O has the genotype to be
OO. There are no antigens but has
antibodies to be A or B.

Rhesus factor or the 'D' antigen is also
found on the surface of the red blood cell.
Those with it are seen to be "rhesus
positive or Rh+" and those without are
"rhesus negative or Rh-". There is a
possibility of having both Rh + and Rh -. A
person who is Rh + will produce antibodies
against Rh - blood cells. A patient with Rh
+can receive blood from someone who is
Rh + or Rh -. But an Rh - can only receive
blood from Rh -.

Knowing your blood type helps during
pregnancy. If the mother is Rh- and the
father is Rh +, the fetus can either inherit
the Rhesus gene from either the father or
mother. Complications (Rh incompatibility)
occur when the Rhesus factor of the fetus
contradicts that of the mother. This is
common when a pregnant woman has Rh -
and the fetus has Rh+. If the blood of the
Rh + baby mixes with the mother’s, it can
lead to the production of antibodies against
the baby’s blood known as Rh-
sensitization. To curb this disease,
pregnant women should always meet
regularly with obstetricians and human
anti-D immune globulin or immunoglobulin
should be administered to those with the
complications.

General Note
*O are universal donors (donate blood to all
blood types).
*AB+ are universal recipients (receive from
all blood types).
*A+ can receive blood from A+, A-, O+ & O-
* A- from A- & O-
*B+ from B+, B-, O+ & O-
*B- from B- & O-
*AB- from A-, B-, AB- & O-
* O+ from O+ & O-
*O- from O-

In Conclusion
Knowing one's blood group helps a lot. It
determines the donor and recipient of blood
transfusion, and also helps in determining
paternity. A person with one blood type or
group can produce antibodies against the
other. For instance, a person with blood
type A makes antibodies against blood type
B. If this person is given blood of type B,
his or her type antibodies will bind to the
antigens on the type B blood cells cause
the blood to clump together. Compatibility
of blood type is necessary before
transfusing blood in times of accidents and
emergencies.

If you Learn from this article please drop a
comment

Very informative. Thanks.

Very important