|
Historical Background
The inherited disorder of hemoglobin (Haemoglobinopathies) are so common in the carrier form and so lethal in the disease form that an explanation for their extraordinarily high frequency is required.
The incidence of Thalassaemia trait varies greatly from country to country. It's extremely widespread and occurs in a line extending through the Mediterranean, the Middle East, the Indian sub-continent and through out South East Asia, in a region including Southern China, Thailand, the Malay Peninsula and many of the islands.
Because the world distribution of the major inherited hemoglobin disorders coincides with that of malaria, it's thought that carriers of the
Thalassaemia gene have some protection from the most severe forms of malaria.
|
|
What is
Thalassaemia - A General Overview
Thalassaemia is a serious autosomal recessive genetic blood disorder. You cannot catch it or develop it. It is inherited as carrier form or as
Thalassaemia Major. One form cannot change into another.
The Carrier has inherited just one Thalassaemia Gene from either parent. A Thalassaemia Major baby inherits two
Thalassaemia genes- one from each parent. Both parents must be carriers in order to have a Thalassaemia Major child.
Carriers are perfectly healthy. The “haemoglobin electrophoresis” blood test can reveal a carrier.
If both partners are carriers, there is a 25% chance at each pregnancy that the child will inherit both their Thalassaemic genes and have Thalassaemia Major. This is a Mendelian inheritance pattern.
A child with Thalassaemia Major is unable to make enough blood cells and develops a severe life threatening
anemia. If this child is not transfused with blood he/she could die in childhood. 80% of Thalassaemia Major births in the UK occur in Asian families.
Besides blood transfusions every month, this child requires daily iron removing treatment that involves 8-12 hours of a pump driven continues injection. This is done at home.
There is no effective cure for Thalassaemia Major. The blood transfusions and the treatment are life long.
Thalassaemia Major can be prevented. A simple blood test done by your GP will reveal if you are a Carrier. You get yourself tested first. If you are a carrier then get your partner tested. If your partner is not a carrier you have nothing to worry about.
Where both partners are carriers, you can still have children. There is a 25% chance at each pregnancy that the child has Thalassaemia Major. You can have the pregnancy tested and find out if the baby is affected. You then have an informed choice of continuing the pregnancy.
Up to 1 in 7 Asians are carriers of the Thalassaemia Gene. The Thalassaemia gene affects particularly people of Mediterranean, Asian or Middle Eastern origin. However, up to 1 in 1000 of the indigenous UK population carry it as well.
The incidence of Thalassaemia Major can be eventually reduced to zero by carriers making informed decisions about having children. It is vital that awareness is raised about the disorder.
|
