'It's in the genes': How sickle cell disease silently lurks across generations

 SCD is a genetic condition that is present from birth and inherited.[iStockphoto]

When Beryl Oyugi welcomed her second child into the world, she had no reason to believe that a hidden gene passed down through generations would change her family’s life forever.

Like many young mothers, she expected the usual challenges of parenthood, feeding, school fees, childhood illnesses and raising healthy children. Instead, she found herself navigating a painful journey of hospital visits, blood transfusions, medication schedules, emotional stress and difficult conversations about genetics that she had never been taught before marriage.

Today, the 32-year-old teacher from Kisumu’s Kachok area is raising two children living with sickle cell disease. Her story mirrors the experiences of thousands of families across Kenya’s Lake Region, where sickle cell disease remains one of the most common inherited disorders.

World Sickle Cell Day was marked last week with health experts increasingly emphasising one message: understanding genetics could be one of the most powerful tools in reducing the burden of the disease.

At the centre of this conversation is Dr Bernard Awuonda, a paediatrician at Jaramogi Oginga Odinga Teaching and Referral Hospital (JOOTRH) and the Kenya Lead for the Consortium on Newborn Screening in Africa (CONSA). He says many families continue to suffer because they do not fully understand how sickle cell disease is inherited.

According to Dr Awuonda, sickle cell disease is not caused by witchcraft, curses, sin, bad luck or anything a parent did wrong. It is a genetic condition passed from one generation to another through inherited genes.

“To develop sickle cell disease, a child must inherit one sickle cell gene from the mother and another sickle cell gene from the father,” explains Dr Awuonda.

“It is what we call an autosomal recessive condition. For somebody to develop the signs and symptoms of sickle cell disease, they must inherit two abnormal genes one from each parent.”

He says every human being receives one gene from the mother and one from the father. Together, these genes determine many inherited characteristics, including whether a child will develop sickle cell disease, become a carrier, or be completely free from the sickle cell gene.

Understanding this inheritance pattern, he says, is critical because it allows families to make informed decisions long before children are born.

Dr Awuonda says that many people do not understand the probabilities involved when carriers have children.

“If both parents are carriers, every pregnancy carries a 25 per cent chance of producing a child with sickle cell disease, a 50 per cent chance that the child will become a carrier, and a 25 per cent chance that the child will be completely normal and free from the sickle cell gene,” he explains.

These percentages apply to every pregnancy independently. “What people must understand is that these are probabilities. They do not mean that if a couple has four children, one will automatically be a sickle-cell carrier, two will be carriers, and one will be normal. That is not how genetics works.”

He says each pregnancy represents a new probability. “A family may have four children, and all four turn out to be carriers. Another family may have three children with sickle cell disease. Another may have one affected child and several unaffected children. Genetics does not distribute itself evenly according to family size.”

This distinction is important because many families become confused when reality does not match what they think the probabilities should look like.

“If a family has two children with sickle cell disease, it does not mean the calculations were wrong. It simply means that the probability happened that way in those pregnancies.”

Risk factors

Dr Awuonda further explains that when one parent is completely normal, and the other is a carrier, none of the children will develop sickle cell disease.

Instead, there is a 50 per cent chance that each child will become a carrier and a 50 per cent chance that they will be completely free from the gene.

If one parent has sickle cell disease and the other parent is completely normal, all children born to that couple will become carriers.

“They will not have sickle cell disease, but they will carry the gene and can pass it on to future generations,” he says.

This is why genetic screening remains a critical public health intervention. One of the greatest challenges in the fight against sickle cell disease is the large number of people carrying the gene without knowing it. Unlike people living with sickle cell disease, carriers usually appear completely healthy.

They attend school, work, marry, have children, and live normal lives without experiencing the painful crises associated with the disease. “Most carriers do not know they are carriers unless they undergo genetic testing. That is why the gene continues to move quietly through generations, “says Dr Awuonda.

Data from newborn screening programmes in Kisumu reveal that approximately one in every five people carries the sickle cell gene. “If you walk through the streets of Kisumu and meet one hundred people, about twenty of them are likely to be carriers,” he says.

Many of them do not know their status, and this means carriers unknowingly meet, marry, and start families together, increasing the chances of children being born with sickle cell disease.

For Dr Awuonda, this is where education becomes crucial. “The goal is not to stop people from marrying. The goal is to empower them with information.”

For Beryl, genetics was something she barely thought about before marriage. Growing up, nobody advised her to undergo sickle cell screening before settling down.

There were no widespread awareness campaigns. There were no conversations in schools about genetic inheritance. There was little information available to young people preparing for marriage. “Back then, before I got married, there wasn’t much awareness about sickle cell disease. Nobody advised us that before marriage we should get screened.” she recalls. 

Like many couples, she entered marriage unaware that both she and her husband were carriers of the sickle cell gene. The reality emerged only after the birth of their second child. “My journey changed when my second-born daughter was diagnosed with sickle cell disease,” she says.

The diagnosis came with fear, uncertainty, and discouraging comments from people around her. “Some people told me she would not survive, while others said she would not manage the painful crises.”

But her daughter survived, through medication, proper nutrition, hydration, and close medical follow-up, the child continued growing.

Then another shock came when her third child was also diagnosed with sickle cell disease. Many people had previously told her that among the four children, only one would likely have the disease.

When her second and third children both tested positive, she struggled to understand why. “The answer, doctors later explained, lay in genetics and probability. “

Blame game

The 25 per cent chance attached to every pregnancy does not guarantee a specific outcome across several children.

Beryl says one of the greatest challenges is the misunderstanding that often follows diagnosis. “In many cases, people assume the disease came from the mother’s side.”

Without proper education, blame begins to emerge. Some fathers distance themselves emotionally, while others question paternity, resulting in some marriages breaking down completely.

Beryl says she experienced some of these challenges. “There was a time my husband struggled to understand how the disease occurred. It reached a point where he questioned whether the affected child was biologically his,” she says.

The situation only changed after testing and counselling. Doctors explained that for a child to develop sickle cell disease, both parents must carry the gene, and that education transformed the family’s understanding.

While the physical effects of sickle cell disease are widely discussed, experts say the emotional and psychological burden often receives less attention.

Dr Awuonda says parents frequently live with anxiety about when the next pain crisis will occur.

“You can have a child who is perfectly fine during the day and then develops a severe crisis at midnight.”

Despite advances in medicine, myths surrounding sickle cell disease remain widespread. Some communities still associate the condition with curses, witchcraft or supernatural forces, while others believe it is contagious.

Dr Awuonda says such misconceptions continue to fuel stigma.

“There are still people who think sickle cell disease is caused by witchcraft. Some people think it can be transmitted through sharing food or physical contact.”

None of these beliefs is true.

Dr Awuonda adds that sickle cell disease is inherited and cannot be spread through touching, hugging, eating together or sharing living spaces.

Despite ongoing challenges, Kisumu County has made significant progress. According to Dr Awuonda, JOOTRH became the first public health facility in Kenya to launch routine newborn screening for sickle cell disease. The county has also introduced Red Cell Exchange services at JOOTRH’s Victoria Annex.

One major concern is access to Hydroxyurea, one of the most important medications used in sickle cell management. Hydroxyurea helps reduce painful crises, lowers hospitalisation rates and improves quality of life. However, its availability remains inconsistent.

Dr Awuonda believes access must be expanded.

According to the World Health Organisation, approximately 14,000 children are born with sickle cell disease in Kenya every year.

Globally, more than 300,000 babies are born with the condition annually. Nearly 100 million people worldwide live with sickle cell disease, while an estimated five per cent of the world’s population carries genes associated with haemoglobin disorders.

In sub-Saharan Africa, the burden remains especially severe, with between 50 and 90 per cent of affected children dying before their fifth birthday in areas where diagnosis and treatment remain limited.

In Kisumu County alone, approximately 1,500 children are born with sickle cell disease every year, representing three to four cases in every 100 births.