SA's first oestrogen metabolism gene test available

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Developed over the past six months in collaboration with integrative, anti-aging and functional medical specialists in South Africa, the test will assist medical practitioners in making clinical decisions that will ultimately lower the risk of breast cancer for all women, but especially those considering or taking hormones such as oral contraceptives and hormone replacement therapies (HRTs).

"Sex steroids, which include oestrogens, have a variable metabolism that is strongly influenced by genomics and environmental factors. If used correctly, genetic testing can prove invaluable for fertility, the management of the peri- and post-menopausal state as well as breast cancer risk profiling," says Johannesbrug-based specialist physician and endocrinologist, Dr Sandeep Bhana.

"Breast cancer is the most frequently diagnosed cancer in women worldwide, comprising 16% of all female cancers. In South Africa, 1 in 29 women are affected. For a tiny 5% of women, breast cancer is inherited in a single gene. For the remaining 95% diagnosed, the disease usually develops later in life between the ages of 55 and 70. Genes, diet, lifestyle and environment are all contributing factors. However, for a significant percentage of these women, their ability to metabolise oestrogen is also contributing factor," says Yael Joffe, dietician and director for DNAlysis Biotechnology.

Identifying HRT risks

HRTs, which offset symptoms of menopause such as hot flashes, vaginal dryness and mood fluctuations, as well as decrease the probability of diseases found in post-menopausal women such as heart disease and osteoporosis, contain high levels of oestrogen. Studies have consistently found that women who use HRTs for five years or more, increase their risk of breast cancer by approximately 35%.

"The risk is highest for women who do not metabolise oestrogen well. If it is not efficiently metabolised and eliminated from the body, oestrogen metabolites accumulate in the tissues and are potentially carcinogenic," says Joffe.

A handful of medical specialists in South Africa dealing with these issues individually approached DNAlysis Biotechnology to develop a test that would provide additional information on which to base their hormone and HRT recommendations.

"The risk for women going onto HRTs is high and these doctors understand that. Their goal is to assess the risk of every woman who walks into their practice. However, there is no blood test that provides insight into an individual's oestrogen metabolism. In addition, family history or the traditional cancer risk pointers - early menarche, late age at first childbirth, shorter breastfeeding - do not offer sufficient insight either," says Joffe.

Approach to gene selection

DNAlysis Biotechnology's approach to gene selection was to identify, from the 40 or so known gene variations related to oestrogen metabolism, a handful of variations that would provide the clearest possible insight into an individual's genetic makeup as well as their ability to metabolise oestrogen.

"This information, coupled with other considerations unique to the individual, means doctors are far better informed prior to prescribing HRTs - the patient's risk is better known and can be managed accordingly. Similarly, women making these lifestyle decisions are now also better informed of their risk."

Affordability and specialist support

The test will cost around R2000 and will be available through a select handful of referring specialists.

"The test will only be available via healthcare practitioners who have completed the necessary training to interpret the findings and offer an informed diagnosis. We are highly committed to expanding our existing network of trained and accredited healthcare practitioners and, as such, offer a training programme to the industry in this regard," says Joffe.

This test is the first clinical test DNAlysis will bring to market this year, having launched two consumer tests, DNADiet and DNAHealth, in 2009.

"It's a new journey for us. Genetics is playing an increasingly important role in diagnosis and holistic treatment of disease, and is an important factor to consider when making diet and lifestyle decisions. It's particularly gratifying to offer a test that has a direct and positive impact on prevention and management of a disease like breast cancer. We hope that within five years this test will be available to every woman in South Africa," says Joffe.

For more information on DNAlysis Biotechnology, its various products as well as its healthcare practitioner training programme, call +27 (0)11 268 0268 or visit www.dnadiet.co.za.