There are an estimated 100 million individuals with hemoglobin S worldwide.
Defined as the inheritance of the single copy of the sickle mutation that results from a single base pair substitution in the gene encoding the beta-globulin chain of hemoglobin.
In the United States there are more than 3 million carriers of hemoglobin S.
In the US approximately 8% of blacks and 0.5% of Hispanics and 0.2% of Caucasians carry hemoglobin S.
Carriers of hemoglobin S are generally asymptomatic and have a normal life span.
Renal manifestations of the most reported complications and include impaired urinary concentration, asymptomatic hematuria, and papillary necrosis.
Carriers of hemoglobin S are at increased risk for splenic infarction, exertional rhabdomyoslysis and renal medullary cancers.
The risk of exercise-related sudden death is 10-30 times higher among hemoglobin S carriers then among non-carriers.
The risk of exercise related sudden death in sickle trait carriers is increased by heat exposure, dehydration and intense exercise.
Patients have more than 50% normal hemoglobin and they are essentially asymptomatic, except under unusual circumstance.
Among African Americans associated with increased chronic kidney disease, decline in eGFR, and albuminuria (Naik RP et al).