How is haemochromatosis inherited?
Inherited disorders are caused by defective genes in the cells which make up the body. Genes, which are made up of DNA, contain the information, the body needs to develop from the egg, and to maintain itself in good working order. Human beings have about 60,000 genes, and every cell in the body except the egg and sperm cell contain two copies of each. One of these copies is inherited from each parent. The disease Haemochromatosis is a recessive disorder. This means that it only develops if both copies of the gene are abnormal. If only one copy is defective an individual will be perfectly well but will be a carrier, about 20% of the population are carriers, This means:

1. If both parents are carriers
(about 1 in 25 marriages), On
average a quarter of the
children will develop
haemochromatosis, half will be
carriers and a quarter will be
normal.

2. If one parent has
haemochromatosis and the
other is a carrier (about 1 in
3,000 marriages) on average
half of the children will
develop haemochromatosis
and the other half will be
carriers.

3. If both parents suffer from
haemochromatosis, (a rare
event, occurring in about 1 in
10,000 marriages) all
the children will inherit two
defective genes and ail
will have haemochromatosis.
It should be emphasized that
the proportions given in examples 1 and 2 are averages for the whole
population. For instance, in any particular family where both parents are
carriers, it would be possible for all children to be affected, all to be carriers
or all to be normal.

What is the Haemochromatosis?
What are the symptoms?
Diagnosis and Treatment - What are the tests?
Diagnosis and Treatment - What is the treatment?
Who should be tested?

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