What does my wife's Hb electrophoresis report indicate?

Q: My 39 years old wife underwent a test called Hb electrophoresis recently. The values of HPLC were - HbAo - 65.4%, HbA2/E - 33.3%, Hb F - 0.5%, unknown peak - 0.8%. Comment in the report was - Hb E Trait. What does it indicate? Is there any serious problem with her? Please advise.

A:Haemoglobin (Hb) is the oxygen carrying protein present in our red blood cells. It is made up of an iron containing haeme molecule surrounded by a protein called globin. Each Hb molecule contains two pairs of globin chains, called alpha (a) and non-alpha - (beta [b], gamma [g], delta [d]) chains. Any defect in the amount or structure of the globin chains can give rise to abnormal haemoglobins and disease states referred to as thalassemias-hemoglobinopathies. An adult normally has the following types of haemoglobins present in blood:

• Hb A – made up of 2 alpha & 2 beta globin chains (a2b2) : 95% of total Hb
• Hb A2 – made up of 2 alpha & 2 delta globin chains (a2d2) : 3% of total Hb
• Hb F – made up of 2 alpha & 2 gamma globin chains (a2g2) : 1-2% of total Hb

Normally we have 2 copies of Hb A gene (Hb A/A). Hb E is an abnormal haemoglobin with a mutation in the b-globin chain. If only one gene is affected it results in Hb A/E (called HB E trait) which is asymptomatic. If both copies are abnormal, it results in Hb E/E and such patients are usually anaemic (have low Hb) and have an enlarged spleen. Please get yourself and your children tested by HPLC as the combination of Hb E with another abnormal haemoglobin can give rise to severe disease. No treatment is required for your wife.