Inheritance of Sickle Cell Anaemia
Picture this; Two people meet, they fall in love and decide to get married. Everything is going smoothly until the children are born. No, the introduction of children is not the actual problem here, since children are generally seen as blessings from God in Nigeria. The state of health of the children is where the problem lies. These children start getting constantly sick from a young age, succumbing to various diseases like malaria and requiring admission for minor disorders like the flu. A simple genotype test would show the children as being SS positive (Sickle cell disease). How is that possible? The parents would go for testing and they would both be confirmed as AS positive (Sickle cell carrier). This is where the problem lies; a lack of awareness of genotypes and genotypic compatibility. This ignorance had led the couples to marriage and procreation, creating a conundrum of sickly children.
What is Sickle cell disease?
Sickle cell disease (SCD)is an inherited disorder of red blood cells where cells assume an abnormal sickle shape instead of the healthy round ones. The red blood cells contain haemoglobin which helps carry oxygen to all tissues in the body. In a person with SCD, the rigid sickle shape of the cells obstruct the delicate blood vessels, limiting blood and oxygen flow and causing a painful crisis. Additionally, the early death of the cells leads to a shortage of red cells causing anaemia.
Some types of SCD are HbSS, which is a more severe form where people inherit 2 genes that code for haemoglobin S from each parent while a milder form called HbSC is where a haemoglobin S is inherited from one parent and C from the other. A person with HbAS is termed as having the trait and union with a fellow carrier could result in a 1 in 4 chance of each pregnancy resulting in an SS offspring. This means all offsprings of carrier couples could end up with sickle cell disease.
Children with SCD occasionally go through painful crises triggered by infections, extreme heat or cold, dehydration, high altitude etc. They are in constant need of blood transfusions and their crises can only be managed in the emergency unit with immediate fluid infusion and strong painkillers (opioids). In some cases, these children develop acute chest syndrome and die young. The only known cure for SCD is bone marrow transplant which is an expensive and dangerous procedure that could lead to lifelong complications.
How can we mitigate SCD?
Education and mass awareness are needed to prevent this killer in Nigeria and Africa. This is important because despite SCD being common among Africans, awareness and education of this genetic disorder is low among a wider proportion of the population.
Growing up, I remembered hearing stories from elderly women about losing over a dozen children in infancy to unknown diseases. This could be as a result of undiagnosed SCD. It is understandable why child mortality was so high during those times, due to a dearth of knowledge of the SCD. However, it is unacceptable to still record a high prevalence of SCD in Nigeria in the 21st century.
The table above illustrates the different genotypes available, the combinations that are compatible and the ones that should be avoided.
Awareness campaigns have reached some rural and urban corners of Africa, educating people on the need for genotype testing, especially before coupling. The chart above displays how mass campaigns through images and banners can be used to raise awareness on genotypic compatibility prior to marriage. However, some communities have not been educated on this while some have but choose not to do these tests. There are, of course, wider issues at play in some communities ranging from poor access to health services that offer these tests, to the inability to afford these tests when available. Nevertheless, there is still a subset of the population that wilfully ignore these warnings because they are in love. They pray for miracles that will prevent them from having children with SCDs and choose passion over sensibility, later regretting this. In such situations, despite the financial and relationship struggles such couples experience from having children with SCD, my empathy is always with the children that never asked for this.
To fight SCD in Nigeria, a multifactorial health promotional approach using education, social campaigns, community outreach etc must be utilized. Active stakeholder engagement is important to provide accessible and affordable testing services to the public. Finally, sensibility must always trump passion, by choosing to go for premarital genotype testing and being willing to separate if couples are both carriers.
rahmanasirblog 