Genetic Condition – HFE – Hereditary Haemochromatosis

Genetic Condition – HFE – Hereditary Haemochromatosis

HFE – Hereditary Haemochromatosis is a common genetic condition in which sufferers have an abnormally high level of iron uptake into various organs in their body. It is an iron overload disorder. HFE – Hereditary Haemochromatosis was also known as Bronze diabetes in the past due to the colour that an affected person may turn without treatment. Early symptoms include weakness, fatigue, abdominal pain and weight loss. If left untreated, HFE – Hereditary Haemochromatosis can lead to skin discolouration, diabetes and heart problems.

 

Inheritance / genetic counselling

HFE – Hereditary Haemochromatosis follows an autosomal recessive pattern of inheritance. A personal affected with this condition has two faulty copies of their HFE gene; one inherited from their mother and the other from their father. If an affected person’s parents had one working copy of HFE and one copy with a mutation, they are referred to as being a carrier of HFE – Hereditary Haemochromatosis. A person with HFE – Hereditary Haemochromatosis can only pass on a faulty copy of the HFE gene meaning that all of their children will either be carriers if they inherit a working copy of the HFE gene from their other parent or at risk of developing the condition if they inherit a faulty copy of the HFE gene from each parent. Siblings of a person with HFE – Hereditary Haemochromatosis usually have a 25% risk of also having the condition, however if their parent also has the condition then 50% of their children are at risk.

 

Molecular genetics

This condition is due to a mutation in the HFE gene, which is located on the short arm of chromosome 6 at location 6p22.2. A gene is made of DNA and DNA is made of four chemicals referred to as bases (A, G, C & T). These bases combine together in a pattern to code for one of 20 amino acids. Amino acids strung together form a protein. There are three common mutations in the HFE gene; C282Y, H63D and S65C.

About 60 – 90% of people with two copies of the C282Y mutation will develop iron overload in their lifetime, whereas only about 5% of people with a C282Y and H63D combination will develop the condition. About 1% of people with two copies of H63D will go onto having iron overload.

 

Prevalence

HFE – Hereditary Haemochromatosis is the most common genetic condition in Australia and one of the most common genetic conditions in Caucasians. HFE – Hereditary Haemochromatosis is uncommon in people with African and Asian decent. HFE – Hereditary Haemochromatosis is more common in men than women.

 

Management

The most common treatment for HFE – Hereditary Haemochromatosis is blood letting to reduce iron levels in the blood.

 

Differential diagnoses

Not everyone with iron overload will have HFE – Hereditary Haemochromatosis. Other types of Hereditary Haemochromotosis include Juvenile hereditary haemochromotosis (also known as hereditary haemochromotosis type 2) and TFR2 – Hereditary Haemochromatosis.

 

Resources:

http://www.americanhs.org/

www.haemochromatosis.org.au

www.haemochromatosis.org.uk

http://www.genetics.edu.au/publications-and-resources/facts-sheets/fact-sheet-47-hereditary-haemochromatosis