Genetic condition awaiting consideration - Ataxia telangiectasia (AT)
Ataxia telangiectasia (AT) is an autosomal recessive condition caused by a change in a gene called Ataxia Telangiectasis Mutated (ATM) on chromosome number 11.
Parents of an affected child will both be healthy carriers, but have a 25% chance of having an affected child in each pregnancy they have.
AT classically presents in early childhood, with mild delay in the motor milestones, clumsiness and frequent falls. This is followed by progressive ataxia (lack of muscle control leading to poor balance and coordination), speech and swallowing difficulties. In time, walking becomes limited as well as the purposeful use of hands (fine motor skills). Consequently, eating, dressing, writing becomes difficult. Children have restricted eye movements and difficulty keeping their heads upright. On average, patients require wheelchair use by the age of 10 and need help with activities of daily living.
One of the features of this disorder is immune deficiency and therefore children are more susceptible to infections. They also have an increased risk of developing leukaemia (cancer of blood cells) or lymphoma (cancer of lymphatic tissue). Less frequently, AT presents as Non Classic, adult onset disease. Although all the above signs may develop, the severity and rate of progression are much milder.
The life expectancy, especially with the childhood onset disease is reduced, although much improved with supportive treatments. These days many individuals survive over 25 years. Death is usually a result of deteriorating lung function and/or major infection.
Have your say on conditions awaiting consideration
If you have any feedback on the genetic conditions awaiting consideration by the HFEA, send us an email and we will discuss your comments at the next Licence Committee.
Email: pgd@hfea.gov.uk
Page last updated: 11 August 2010