First Gene Located for Testicular Cancer

Tuesday 1 February 2000

Scientists have located a gene which increases men’s risk of testicular cancer by up to 50 times - and is inherited from their mothers.

The research, which is published today (1 Feb) in Nature Genetics, means that scientists now know that this gene is on a particular chromosome, the X chromosome, and are a step away from identifying it.

They believe the discovery will help them in the treatment of the disease and other forms of cancer.

Testicular cancer is the most common cancer in men aged 15-40 in the UK, affecting more than 1,400 people in the UK every year. The newly located gene, which has been called TGCT1, makes men who carry it more susceptible to testicular germ cell tumours (TGCT) which make up 95 per cent of all testicular cancer cases.

Institute of Cancer Research scientist, Professor Mike Stratton, who is funded by The Cancer Research UK, says:

"TGCTI looks to be the first of an unknown number of genes - almost certainly more than three - which predispose men to the disease. At the moment we simply do not know what percentage of testicular cancer cases are caused by an inherited genetic susceptibility but some estimates have put it as high as 20% of all cases."

Scientist Dr Doug Easton of The Cancer Research UK's Genetic Epidemiology Unit, Cambridge University says:

"Once the gene has been identified, we will be able to distinguish men at high risk of the disease, who can then be screened. This should allow the disease to be detected earlier, and be treated successfully with less aggressive chemotherapy."

It should also lead to a greater understanding of the biology and genetics of testicular cancer itself - which could help in the treatment of other cancers.

"Testicular cancer is particularly susceptible to chemotherapy -which means it is successfully treated in more than 90 per cent of cases," adds Professor Stratton, who

led the team that discovered the breast cancer susceptibility gene - BRCA2 - in 1995. "And, if we can find out why this is, we might be able to make other cancers equally sensitive."

The testicular cancer research team has discovered that the faulty gene lies on Xq27- a small region on the X chromosome. This means it is inherited by the patient’s mother, who in turn inherited it from either her mother or father.

Researcher Professor Timothy Bishop of the Imperial Cancer Research Fund Genetic Epidemiology Lab in Leeds says:

"We have also found that TGCT1 is more likely to be involved in families in which a man had an undescended testicle - which we already know is one of the risk factors for TGCT. What’s more, we discovered that families of men who had cancer in both testicles were even more likely to have TGCT1."

The UK scientific team worked with colleagues in Norway, Germany, Australia, Ireland and Canada to study a total of 134 families with two or more cases

of testicular cancer. Out of these families, 87 included two brothers who both had testicular cancer.

Members of the research team will now continue their work to isolate TGCT1, which they believe may take another two to three years. In parallel with

this, they are also looking to locate other inherited testicular cancer genes.

To help them in their work, they are urgently appealing for volunteers with two or more cases of testicular cancer in their family to come forward.

Anyone who can help should write to Dr Robert Huddart, Academic Unit of Radiotherapy and Oncology, The Royal Marsden NHS Trust, Downs Road, Sutton, SM2 5PT.

Professor Bishop adds, ‘We have a lot of work ahead of us because knowledge of TGCT1’s function may help target research into the causes of the increase in incidence of testicular germ cell tumours over the last century."

The number of men in England and Wales who develop the disease increased by more than 80 per cent between the early 70s and early 90s from around 700 to 1,300 annually. Doctors are baffled as to why this is.

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For more information, or to speak to a patient, please contact:-

The Institute of Cancer Research press office, Tel: 0171 970 6030 or email:

Iain Foulkes, Imperial Cancer Research Fund press office, 0171 269 3611 or 0778 841 5475

Sarah Page, Cancer Research UK press office, 0171 317 5017 or 0468 992 023