Test Details: Haptoglobin (Hp) is a haemoglobin (Hb) binding protein whose major function is to prevent heme-iron mediated oxidation. Hp is characterised by a genetic-polymorphism resulting in three genotypes (Hp 1-1, Hp 2-1 and Hp 2-2) which results from expression of two different alleles (Hp1 and Hp2) of the Hp gene. Patients with the Hp2-2 genotype and diabetes have a greater risk of heart attack or stroke than those with the Hp1-1 genotype. This test helps in therapeutic decision making for cardiac diseases.