Q: My daughter who is 14 months old has been diagnosed with Thalassaemia major. Currently, her haemoglobin level is between 8 to 9. Doctor says that they will start blood transfusions only if her haemoglobin level falls below 7. My wife and me are Thalassaemia minors. We came to know this only after our daughter was diagnosed. I am thinking about stem cell transplantation to cure the disease. Though we have not stored her cord blood but I have my cousin who has stored the cord blood of his daughter. How can we proceed further with this? What is the way to match the blood?

A:A. Thalassaemias are a group of genetic diseases caused by the production of abnormal haemoglobin. Haemoglobin comprises two beta (beta)-globin and two alpha (alpha)-globin chains, their production being governed by 2 beta and 4 alpha genes respectively. In beta-thalassaemia, the production of beta-chain is abnormal while in alpha-thal it is the alpha-chain. When only one beta-globin gene is affected (thal minor or trait or carrier or heterozygous), it results in mild anaemia not requiring treatment but the involvement of both genes results in severe disease (thalassaemia major or intermedia) requiring regular treatment and follow-up from infancy. Persons with thalassaemia minor have only mild anaemia (slight lowering of the haemoglobin level in the blood). It is a clinically benign disorder and thus your wife and you were not even aware of your carrier status. The importance lies in the fact that if both parents are carriers (i.e. carry one abnormal beta-gene), an offspring may co-inherit a beta-thalassaemia gene from both the parents making it homozygous resulting in a medically significant thalassaemia (beta-thalassaemia major). This probability is 25% in each pregnancy. Stem cell transplant (SCT) is the only known curative treatment for thalassaemia but is done only in selected patients as the presence of hepatomegaly, portal fibrosis and ineffective chelation prior to transplant, all affect the outcome. The event-free survival rate for patients who have all 3 features is 59%, compared to 90% for those who lack all 3. Even though blood transfusion is not required after a successful transplant, some patients need continued chelation therapy to remove excess iron. It is a difficult choice to make between standard therapy and SCT for parents of patients with severe thalassaemia as the 15-year cardiac disease-free survival rate for patients receiving standard therapy exceeds 90% and is similar for those without risk factors. The long-term outcome for transplant patients, including fertility, is not known but the cost of long-term standard therapy is higher than the cost of transplant. The possibility of developing cancer after SCT should also be considered. SCT is being done at several centres in India but the largest series is from Christian Medical College, Vellore, Tamil Nadu. You can go to the CMC website and contact the Department of Haematology directly.