Screening · 4 min read
Blood group and genotype: what they are, and why every Nigerian should know theirs
The difference between the two tests, why genotype matters especially before marriage or pregnancy, and how to actually get tested.
By the TarragonHealth editorial team
Two different tests, often confused
Blood group (A, B, AB or O, plus rhesus positive or negative) determines whose blood you can safely receive in a transfusion or emergency. Genotype (AA, AS, SS and rarer combinations) reveals whether you carry the gene for sickle cell disease. They answer completely different questions, and knowing one tells you nothing about the other.
Why genotype matters so much here
Nigeria carries one of the highest rates of the sickle cell gene in the world; a large share of the population carries AS (the trait, generally healthy) without knowing it. Two AS carriers having a child together have a 1-in-4 chance, each pregnancy, of a child with SS, sickle cell disease. Knowing your genotype before marriage or pregnancy turns that into an informed choice rather than a discovery after the fact.
Carrying the trait isn't the same as having the disease
AS (sickle cell trait) is not sickle cell disease; most people who carry it live entirely normal lives with no symptoms. It only becomes a serious consideration for the children of two AS (or one AS, one SS) parents. Discovering you're AS is information for family planning, not a diagnosis to be alarmed by.
How to actually get tested
Both are simple blood tests at any decent laboratory, results typically back within a day, no special preparation needed. If you've never checked either, or you're planning a marriage or pregnancy and don't have a written result you trust, it is one of the cheapest, most consequential pieces of information you can gather about your family's future.
This article is general health information, not medical advice, a diagnosis, or a treatment plan. Always talk to a doctor about your own situation, and if you feel seriously unwell, go to a hospital now.