mind helvetica, physician sans-serif; font-size: 1em; background-color: #92d2dd; border: medium solid #333333; text-align: center;">One can be affected by ataxia telangiectasia with parents who are not.

cialis helvetica,sans-serif; font-size: 1em; background-color: #92d2dd; border: medium solid #333333; text-align: center;">Each parent is carying an anomaly (in most cases).

AT is autosomal and recessive

Autosomal

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that equally affects the two sexes.

Récessif

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In our genetic heritage, we all have two alleles of the same gene, ie twice the copy of the gene. One comes from our mother and one from our father.

A gene is called "dominant" when one altered allele is sufficient to express the abnormality. In this case, the parent who transmit it is ill too.

A gene is called "recessive" if both abnormal copies of it are necessary to express a disease. In this case, neither parent has an anomaly whereas they are both carriers of a defective copy of the gene. This is the case of ATM: it requires that each parent carries an altered allele and transmit it to their child.

So there is 1 in 4 chance that the couple had a child with ataxia telangiectasia. In rarer cases, an allele may be altered during design, giving the same result.

Genetic counseling and the opportunity to make a prenatal diagnosis is possible, but only if a child is already concerned within the family and whether the mutation causes the disease is identified.

link helvetica, physician sans-serif; font-size: 1em; background-color: #92d2dd; border: medium solid #333333; text-align: center;">In Europe, 1 in 100 000 people suffers from ataxia telangiectasia.

There are no ethnic, economic, geographic or education criteria to be suffering from AT. Girls and boys are affected the same way.

In France

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Two recent French studies statistics (see research ) suggests that there are currently about 150 cases in France of patients with AT. Given the life expectancy of these patients and unidentified cases, the average prevalence is approximately 1 / 100, 000, value considered valid throughout Europe.

Other countries

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Figures:

• 1 / 300 000 in the United Kingdom according to AT Society. (english AT charity)
• 1/40 000 (in the USA) according to the americans of AT Children Project (US charity), maybe more if we consider all children, especially younger ones, who are deceased but have not been properly diagnosed.

These figures seem very different, varying by a factor of 10. However, the English estimate seems low taking into account that about 1% of the population is carrying the defective ATM gene and that it is recessive (see Transmission). The U.S. estimate seems a bit high but we do not know on what basis it references.

Note that these very low probabilities are significantly increased when inbreeding, and this for all the recessive diseases. It is obvious: there is a much stronger chance of finding the alteration of a gene within a family, so both in a man and a woman being relatives, even distant.

In all cases, these statistics are impressive at first sight and exacerbate feelings of loneliness. Are we really alone? ... Well not more in facing the disease (7000 identified rare diseases) than in considering medical research: there are 250,000 new cases of cancer each year in France and the ATM gene may play a role for some of them. Therefore, it is regularly under the microscope objectives of researchers ..