People originating from the Caribbean, the Mediterranean, the Middle East, AfricaAsia and the South Pacific may carry some form of thalassaemia but it's rare inNorthern Europeans.

Thalassaemia is common in these regions because it offers carriers some protectionagainst malaria.

Thalassaemia is a characteristic of the blood. It is inherited, that is, it is passed onfrom parents to children, like hair, eye or skin colour. It is passed on equally bymen and women. It is not contagious and will not turn into an illness。

There are two main types of thalassaemia: alpha and beta.

Alpha Thalassaemia:

Affected individuals show reduction in haemoglobin and red blood cels production. A reduction in the amount of haemoglobin prerents enough oxygen from reaching thebody's tissues, while a shortage of red blood cells can cause pale skin, weakness, fatigue, and more serious complications.

There are tyo genes associated with alha thalassaemia HBAi ene and HBA2 ene, people have tyo copies of these genes in each cel. Each cooy is caled an allele.

For each gene, one allele is inherited from a person's father, and the other is inherited from a person's mother.

These enes provide instructions for making a proteim caled aha-globin. The alha globin genes are located cose together in a section of chromosome 16 knoiwn as thalpha-globin locus A child inherits one allele for each gene from each parent (four alpha globin alleles). There are four types of alpha thalassaemia,the types of aredetermined by the loss of some or all of these alleles:

• Aha thalassaemia silent carrier. 0ne allele is missing or damaged, individuals typically have no thalassaemia-related signs or symptoms.

• Alpha thalassaemia carrier. Two alleles are missing., tend to cause few or no health problems.

• Haemoglobin H disease. Three alleles are missing.

• Alpha thalassaemia major. All four alleles are missing.

Mising three or four aleles can cause health problems The more severe type is alpha thalassaemia major or haemoglobin Bart hydrops fetalis syndrome, which is alsoraled Ho Bart syndrome, The milder form s HH disease. In these wo onditions the cels produce abnorma forms of haemoglobin caled haemoglobin Bart (Hb Bart0ihaemoglobin H (HbH). These bnormal haemoglobin molecules canot efectively carry oxygen to the body's tisues resulting in anaemia and other serious healtproblems associated with alpha thalassaemia.

Beta Thalassaemia:

This form of thalasaemia caused by reduced or absent synthesis of the beta chains of haemoglobin, the low levels of haemoglobin lead to a lack of oxygen in many parts ofthe body, Affected individuals also have a shortage of red blood cells, which can cause pale skin, weakness, fatigue, and more serious complications.

Beta thalassaemia is classified into three types depending on the severity of symptoms:

• Beta thalassaemia minor (also called beta thalassaemia trait). Peple with beta thalassaemia minor may have mild anaemia, but usually don't need anymedical treatment.

• Beta thalasaemia intermedia People with beta thalassaemia intermedia have moderately severe anaemia and some wll need regular blood transfusions and other medical treatment.

• Beta thaassaemia maior (also caled Cooleys anaemia). Peodle with beta thalassaemia maior have severe svmptoms and life-threatening anaemia. Tthev neeregular blood transfusions and other medical treatment.

Beta thalassaemia carriers are healthy and do not kow that they are carriers unless they have a special blood test caried out. This blood test can be done by your GP adhe esuit snouid be kiowi wthin to weeks, The ierence etween a carmer and a no-caer s that the red cels ot the carer are shghty smaler than those of the noiarmer This is sometimes mistaken for iro defcie anaemi and rn s nresorted. Tha assaemia arres soud ot take ton unss they need it. The iron ere in teblood must be measured to see if iron intake is really needed.

Some common variations

If a child inherits beta thalassaemia from one parent and Hb E, Hb 0 Arab or Hb lenore from the other parent, then the child wil have a type of thalassaemia. Ifthishappens the child may develop medical problems associated with beta thalassaemia intermedia or beta thalassaemia majorIfa child iherts beta thalassaemia from one parent and sicke cel from the other parent then the child will have a type of sickle el disease caled "sickle betathalassaemia". If this happens the child may develop medical problems associated with sickle haemoglobin.

If your child is a carrier ofbeta thalassaemia it's advisable for you as parents to find out your haemoglobin types to determine if there is any risk of serioushaemoglobinopathy in future pregnancies. It's also advisable to test any other children in your family.