Thalassaemia also known as Mediterranean Anaemia Μεσογειακή Αναιμία is a common inherited condition affecting haemoglobin – the oxygen-carrying molecule found in red blood cells. The haemoglobin molecule is made up of two proteins, alpha and beta globin.
Surprisingly, it has been estimated that about 7 per cent of the world’s population are carriers of various types of thalassaemia, or haemoglobinopathies. This high frequency is almost certainly the result of human adaptation and natural selection to malaria infections.
When either of these proteins is produced at lower than normal levels, red blood cells become unsound resulting in severe anaemia, a condition that must be treated with regular blood transfusions every 3-4 weeks.
Blood transfusions usually start in early childhood and become part of one’s life all the way to adulthood. Lifelong blood transfusions are life threatening as toxic levels of iron build up, inevitably leading to problems with the liver, heart and other vital organs.
Treatment to remove the excess iron from the body is vital from an early age, to prevent these life-threatening complications.
It is a common misconception that thalassaemia is largely confined to people of Mediterranean background, but in fact thalassaemia is a condition seen worldwide.
Studies indicate that thalassaemia occurs at a high frequency stretching from North Africa, Mediterranean region, through to the Middle East, the Indian subcontinent, to South and East Asia.
Surprisingly, it has been estimated that about 7 per cent of the world’s population are carriers of various types of thalassaemia, or haemoglobinopathies.
This high frequency is almost certainly the result of human adaptation and natural selection to malaria infections.
It is well documented that malaria had a severe effect in terms of both morbidity and mortality on human populations in antiquity.
It killed, or debilitated, people to the extent that it altered the structure of human populations as well as changing human settlement patterns.
Fortunately for carriers of thalassaemia, in particular young children, they were naturally protected against the lethal form of malaria.
Given that children with this trait survived following an infection, they could then pass their natural resistance – the gene for thalassaemia – to their children and so on.
Over thousands of years, it’s not surprising to see how this trait became very common in regions where malaria is or was once widespread.
Today, we see 15 percent of both Greeks and Cypriots are carriers of thalassaemia. These are the highest frequencies of thalassaemia genes found today in any European population. Many Greek Australians carry thalassaemia, but most do not know it until they have an affected child. Being a carrier of thalassaemia has little if any impact on one’s health.
The most serious cases arise when two carriers of thalassaemia have children. Children born to two parents with the thalassaemia trait have a one in four chance of suffering from Thalassemia Major, or life-threatening anaemia.
It has been estimated 300,000 severely affected babies are born each year worldwide. Sadly, many of these children are born in less developed countries with inadequate infrastructure to support them.
With previous and current migration trends from endemic regions, thalassaemia is being seen with increasing frequency in many parts of the world, including Australia.
There are approximately 500 thalassaemia patients in Australia, requiring regular blood transfusions every month. Not surprisingly, over 60 percent of adult patients are Greek, Cypriot or Italian.
However, it is no longer a condition that only affects people of Mediterranean background. Children from recent refugees represent the largest number of thalassemia patients.
Alarmingly, international experts and public health organisations from under developed countries have expressed concern over the increasing rate of thalassaemia patients, warning that thalassaemia will soon become as devastating as AIDS.
In India alone, 10,000 thalassaemia patients are born each year. The same is also true for Pakistan, Bangladesh, Thailand and Indonesia. In Cairo, the Head Clinician Dr El-Beshlawy at the Paediatric Hospital cares for over 7,000 patients and a platoon of 40 doctors and nurses work to keep these patients alive!
In Australia, the annual cost of providing the necessary level of care has been estimated to be as much as $120,000 per patient, which equates to $60 million dollars per year for 500 patients.
Greece, a country of only 11.3 million has 3,500 patients, while Cyprus, a population of only 800,000, has 800 patients. You can quickly see how caring for thalassaemia patients could very quickly deplete the health care budget of any developing country.
Countries such as Cyprus, Greece and Italy were amongst the first to establish successful national screening programs for thalassaemia. One of the most successful campaigns to date was initiated in Cyprus.
As a consequence of the unanimous support from physicians, parents, politicians, and the head of Church, Archbishop Chrysostomos, a mandatory pre-marital certificate was implemented in 1983.
This certificate issued by the Thalassemia Centre in Nicosia stated that the individual had been screened for thalassaemia and counselled at the Centre.
The outcome of the pre-marital certificate allowed the couple time to decide on the best reproductive option.
As a consequence, the number of babies born with thalassemia dramatically dropped from 80 per year to nearly zero.
The success of this prevention program quickly gained international recognition and is now modelled by a number of countries around the world.
In Australia, a mandatary pre-marital certificate would be very difficult to implement due to cultural difference and also on the grounds of ethical and legal issues.
Instead prenatal screening is performed to determine whether or not the pregnancy is affected by thalassaemia.
For many couples this may be a difficult time to decide on the most appropriate reproductive option.
For the hundreds of thousands of patients born each year, bone marrow or cord blood transplantation is the only cure available, but it depends on finding a compatible donor, which is often not possible or may take years to find. One exciting possibility is the use of gene therapy to treat thalassaemia.
This procedure relies on the use of a genetically modified virus to introduce the corrected gene into the patient’s stem cells. Gene therapy has clearly been demonstrated to be effective in a limited number of clinical trials, but despite positive results, there are concerns regarding the safety of this procedure.
While the Murdoch Children’s Research Institute is currently addressing these safety concerns, it is clear that it is necessary to also broaden research into other strategies that do not pose any risks.
Our research group at Murdoch Children’s Research Institute has produced a number of unique resources that has helped to narrow down our search for a more effective treatment. Our research group, as always, is heavily reliant on Government funding to further develop our research, but sadly funds are limited and we remain reliant on ongoing support from philanthropic organisations such as Radiomarathon, The Greek Conference and other fundraising events.
Clearly, thalassaemia is a significant healthcare problem in Australia and it is a massive problem worldwide. Finding a cure will require commitment and compassion, and without science, we can’t do anything.
Dr Jim Vadolas is a medical research scientist located at the Murdoch Childrens Research Institute, Royal Children’s Hospital, Melbourne. The overall aim of his research is to discover and develop novel therapeutic strategies for thalassaemia. He is currently an Executive Committee member of the Australasian Gene Therapy Society and is also a Executive Committee member for Thalassaemia Australia.