Haptoglobin Genotypes And Longevity Among The Ghanaian Population

Haptoglobin (HP), an acute phase glycoprotein with antioxidant, anti-inflammatory and immune-modulatory functions may be an excellent candidate gene to investigate human longevity. The gene is polymorphic and the proteins expressed have different functional capacities due to their distinct biochemical and biophysical properties. The study aimed at determining the possible role of haptoglobin genotypes as genetic markers for longevity. One hundred and thirty three healthy elderly people above 50 years were recruited for the study. The average age of 37 (28%) males was 70.9 years and 96 (72%) females was 75.7 years. Blood samples were collected from participants for hematological analysis, HP genotyping and determination of oxidative stress. A positive correlation between superoxide dismutase activity and age (p = 0.002) was observed in this study population. A negative correlation was observed between age and total white blood cells (p = 0.020), age and neutrophil (p = 0.028), age and platelet counts (p = 0.006). HP1 and HP2 allelic frequencies were found to be 49.5% and 50.5%. Genotypic frequencies for HP2-2, HP2-1, and HP1-1 were 38%, 25% and 37% respectively, showing a departure from the Hardy-Weinberg equilibrium. The HP1 and HP2 genotypic polymorphisms did not appear to influence longevity in the Ghanaian population and none of the genotypes conferred a survival advantage.