Every two minutes, a child is born with sickle cell disease. Most of these children,
especially if they live in low and middle income countries, will die within the first few years
of life, often before the diagnosis is known. Sickle cell disease impacts millions of people
around the world, yet it is rarely prioritized in global health research, advocacy, or funding.
Sickle cell disease is a genetic blood disorder that affects hemoglobin, the protein inside red
blood cells that carries oxygen to tissues throughout the body. In a healthy person,
red blood cells are round and flexible, allowing for smooth travel through small blood vessels and
effective transportation of oxygen to where it is needed. In a person with sickle cell disease,
however, many red blood cells are crescent shaped - like the farm tool known as a sickle. These
sickled red blood cells are hard, sticky, and inflexible. They are unable to travel through
the bloodstream efficiently, often getting stuck and slowing or blocking the delivery of oxygen.
Compared to a healthy red blood cell which has a lifespan of 120 days, sickled cells only live for
10 to 20 days, resulting in anemia, a shortage of red blood cells in the body. One of the
most common and debilitating symptoms of sickle cell disease is sudden, intense episodes of pain
caused by the lack of oxygen. This significantly impairs the daily life of sickle cell patients,
since they may need frequent hospital visits for pain management. Sickle cell disease can
and does affect all parts of the body. Stroke, increased risk of infection, and
chronic damage to the heart, kidneys, and lungs are just some complications from the disease.
Sickle cell disease is caused by a single genetic mutation that affects hemoglobin.
Genes are sections of DNA that provide instructions for individual characteristics,
and we inherit one copy of DNA from each parent. For recessive conditions like sickle cell disease,
two abnormal copies of the gene are needed to pass down the disease. A person with only
one copy of the abnormal gene has the sickle cell trait and is a carrier of the disease.
Although they have no symptoms, they run the risk of passing down the gene to their
children. When each parent carries one copy of the abnormal gene, there is a 1 in 4 chance
that their child will have sickle cell disease. Why does this mutated gene continue to persist in
the gene pool if it has such dangerous effects? The sickle mutation spread generations ago as a
protective adaptation against malaria. Individuals with sickle cell trait have slight differences in
their red blood cells that prevents severe malaria and provides a survival advantage. Malaria is
common near the Equator, and for this reason, many people with the sickle cell trait have genetic
origins from this region of the world. Sickle cell disease affects India and sub-Saharan Africa the
most: in these areas, as much as 25 percent of the population can pass down the disease.
There are simple and effective ways to prevent sickle cell disease and treat most of its
complications. Because symptoms can begin as early as the first year of life and are often fatal,
the first step is diagnosing sickle cell disease early. While newborn screening
is common in high-income areas, it is not available to low income regions,
such as sub-Saharan Africa and India. As a result, many children die from complications that are
unknowingly caused by sickle cell disease and thus not accounted for in global health statistics.
Starting medication immediately can reduce nearly all the symptoms associated with the
disease and increase life expectancy. Hydroxyurea is an inexpensive and effective medication for
sickle cell disease that increases the quantity of fetal hemoglobin. As a result, red blood cells
are bigger, rounder, and less likely to form into the sickle shape. Despite these solutions, newborn
screening and hydroxyurea are not available for most people born with sickle cell disease
because sickle cell disease is not considered a global health priority. Programs around the
world have focused more on preventing and treating other conditions, such as HIV and tuberculosis,
leaving sickle cell disease invisible within the global health landscape. In the field of science,
however, sickle cell disease has increased in visibility, with the rise of new scientific
advancements. A group of technologies collectively known as gene therapy can directly fix the genetic
mutation that causes sickle cell disease. CRISPR Cas9 gene editing is just one example,
but its use is still undergoing clinical trials. While these possibilities are exciting,
basic solutions to the disease must be accessible throughout the world. Sickle cell disease first
needs to be recognized and prioritized as an important global health problem with collaboration
from governments, health organizations, industry, and academia. By doing so, every person with
sickle cell disease can have the potential to live healthy lives regardless of where they are born.