How To Choose a Genetic Testing Provider [SlideShare]

How To Choose a Genetic Testing Provider [SlideShare]

Confused when choosing a genetic testing provider? You came to the right place! This post aims to provide the answers to questions you may have when deciding which genetic testing provider is best for you.

Common Concerns When Choosing a Genetic Testing Provider

“I’m concerned about my risk of cancer and looking for a genetic test. How do I find a provider that not only gives the best value for money but also provides robust testing?”

Since the BRCA1 and BRCA2 gene patents were challenged at the Supreme Court, a number of companies offering testing for breast cancer increased substantially. Prices vary dramatically starting from $99 at 23andme to north of $3500 at Myriad Genetics. Here, we will explain to you the potential pitfalls that you can avoid when selecting a genetic test. It all boils down to: you get what you pay for.

To get you started, here are a few yardsticks that you can use to evaluate the test:

  1. Number of genes being analyzed
  2. Number of markers being analyzed
  3. Cost of the test

1. How many genes are being analyzed?
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(Image source: Image: http://www.nature.com/icogs/primer/common-variation-and-heritability-estimates-for-breast-ovarian-and-prostate-cancers/)

Although the BRCA1 and BRCA2 genes are most strongly linked to breast and ovarian cancers, these genes account only for 10% of all breast cancer cases, and about 25% of all ovarian cancers. A recent large scale iCOGS study identified that risk of breast cancer is determined by at least 76 genes that together explain about 50% of disease heritability – i.e. genetic factors explaining risk of breast cancer. Ovarian cancer is even more complicated as 78 genes account only for 40% of heritability. Furthermore, even for women carrying  BRCA1 or 2 mutation the risk and severity of disease is affected by 10 and 15 additional genes, that are collectively called modifiers.

What does this mean for me?

If the test analyzes only the BRCA1 and BRCA2 genes you will get an incomplete picture of your disease risk because mutations in other high risk genes CHEK2, XRCC2, BRP1, p53, PTEN and many others remain unknown. Recognizing this fact, many companies are creating genetic tests that include more genes to improve the probability of detection for disease causing mutations. Getting negative result for BRCA1 and BRCA2 genes does not mean that you are out of danger.

“Maybe testing for BRCA1 and BRCA2 genes is good enough for me?”

Not really – if you were “cleared” of BRCA mutations, but in fact carry another high risk mutation elsewhere your physician will assume that you do not need close monitoring, so disease might be detected too late reducing the chances of survival.

2. The amount of markers being analyzed in the cancer predisposition genes

Each gene has multiple variation, some are common while others are rare. The 23andme test includes three most common BRCA mutations, as well as 8 additional variations linked to risk of breast cancer.

genetic-testing-tips-23andme

(Image Source: https://www.23andme.com/health/BRCA-Cancer/techreport/)

According to public genetic databases, more than631 disease causing mutations were found in theBRCA1 gene, and 632 in the BRCA2, and in reality many more mutations exist in population.

For technical reasons it is impossible to test for all these mutations with inexpensive SNP arrays used by 23andme and many other providers. Therefore, more expensive tests offered by the Myriad and other providers use gene sequencing technology that reads your genes anew and can identify all known as well as novel mutations.

Although sequencing is much more costly, it is also more robust and informative as it reduces the risk of the false negative result – i.e. saying that you are “out of the woods” when in fact you are at risk.

What happens when a new disease risk gene is found? How my disease risk is affected by this discovery? What about my risk for colon cancer or melanoma?

If you had a specific “breast cancer” test done by SNP array or sequencing of a pre-defined set genes, your DNA will have to be retested again to include the new markers/genes. With whole genome sequencing, and to a lesser extent exome sequencing, your test result can be easily updated by re-running the analysis on a computer with no additional cost and delay.

You should also realize that these panels are “organ or disease specific” – i.e. they predict a specific disease. It is very important to know your risk of breast cancer but there are many other complex diseases such as stroke, diabetes and many others that can be prevented or ameliorated with the knowledge of your inherited predisposition.

Although the whole genome sequencing is much more costly at the moment, at least $5000 depending on a provider, you will save money in the long run by getting complete and much more comprehensive health assessment.

3. Does your insurance cover your genetic test?

If you could avail of an option to save on the expense of a genetic test, wouldn’t you consider it? We are constantly looking for ways to save by using “free” healthcare services – i.e. only the tests covered by private or public insurers.

Genome sequencing is not yet covered by insurers – it is too expensive to justify the coverage for masses, though exceptions have been made for specific cases. Insurers rarely cover even inexpensive SNP arrays.

If you are among the lucky ones for whom genetic testing is covered by insurance, there are a few things to consider:

  1. An insurance company will cover the least expensive option, and by proxy the least informative test. So you will get what you are paying for – i.e. very little.
  2. If your insurance company is paying for the test, they will also know your test results. Do not be scared of insurance knowing your genes – in most jurisdictions insurance companies cannot deny or change your premiums because of your genetic test results.  If you are American citizen you are protected by the Genetic Information Nondiscrimination (GINA) act, or its equivalent in other developed countries. However, if you are unhappy with your insurance provider and would like to switch, you may face difficulties of finding alternative provider.

How to work around the insurance issue

First and foremost, make sure you have life and health insurance before taking any test, not only for yourself but also for your immediate family members. It is advised not to exceed the $1M in total coverage.

Second, select the test provider that you desire, and then contact insurance company to cover, at least partially, the cost of testing.

Third, if you receive negative test results you may try to negotiate with insurance provider to reduce your premiums. If you get a positive test result the insurance company is obliged to keep your coverage at prior premiums and reimburse you for closer monitoring and additional screening which otherwise will not be available to you.

Conclusion – You’ve taken the first step

Even bad news is good news – the knowledge of the inherited risk will allow you to improve your chances of survival substantially! It will be well proven that non-invasive monitoring and preventative treatments (anti-hormonal therapy or surgery) will improve survival for high risk individuals, so you can save a lot of pain and suffering for yourself by getting tested.

Where to find more information on getting a genetic test

Hopefully we answered your questions on how to approach genetic testing and you found our tips useful. If would like to read more, please check this related post: “5 Factors to Consider When Choosing a Genetic Test”.

About the Author: Ruslan Dorfman.

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