Things to Ask a Genetic Counselor About XLH

If you are set to meet with a genetic counselor regarding an X-linked hypophosphatemia (XLH) diagnosis, you probably have a number of questions running through your head but aren’t sure if they cover all you need to address.

Here is a list of questions, with background information, that might be helpful for the appointment.

Pre-diagnosis questions

Depending on your or your child’s symptoms and the results of various tests, your physician might suspect XLH and recommend that you seek genetic counseling. Questions that might provide useful information for you and your family include:

What kind of test looks for XLH?

XLH is a genetic disease, so a DNA sample will be necessary for genetic testing to confirm a diagnosis. There are a number of different ways a doctor can collect DNA, including from a blood sample (the most common way), a swab of the inside of the cheek, or a saliva sample. The method of analysis used for DNA testing can also vary.

Are there follow-up tests if a first test is negative for XLH?

If the test comes back with a negative result but XLH is still suspected, it is important to know if additional tests might help. Each type of genetic test looks for different types of mutations. Some look for a deletion or duplication of an entire gene, while others look for small deletions or duplications within the gene (having a small set of instructions either missing or copied twice). Still others will look for changes at the individual nucleotide (the building blocks of DNA) level. If the test that was ordered looked at larger segments of the gene, it may have missed individual nucleotide changes. A new test might be more sensitive at detecting these changes.

If the test your child took was already highly sensitive, but wasn’t positive for XLH while the symptoms still seem to be, you might be dealing with a disease with similar symptoms, such as Pyle disease, osteomalacia, or hypophosphatasia. The genetic counselor may recommend additional testing for these disorders.

How much does the testing cost?

The cost of genetic tests can vary widely depending on the laboratory doing the analysis, the complexity of the test, and how much your insurance covers. Some organizations may be available to help pay for some or all of the cost of testing.

Will my insurance cover the cost?

It is important to know whether your insurance will help with the cost of testing before you proceed. Most insurance companies will cover a genetic test recommended by a physician. However, preauthorization may be necessary in some cases.

How long does it take to get test results?

The amount of time it takes to get test results can vary depending on the type of test given and the laboratory doing the analysis. The genetic counselor should be able to give you an estimate of time needed.

Will an XLH diagnosis affect my family’s ability to qualify for insurance in the future?

People with genetic disorders report being more likely to be denied insurance coverage or be offered it at a much higher premium than do people without a genetic disorder. It is a good idea to discuss insurance options with your genetic counselor.

Could a diagnosis of XLH increase discrimination?

A legitimate concern in considering genetic testing is that people or companies may discriminate against someone with a genetic disorder. In the U.S., the Genetic Information Nondiscrimination Act (GINA) is designed to protect those with genetic diseases. A genetic counselor may be able to give guidance about types of discrimination faced by people with XLH, and provide tips on how to deal with it.

Postdiagnosis questions

If the results of a genetic test for XLH have come back positive for you or your child, follow-up questions that could be helpful at the genetic counseling appointment include:

Does XLH run in my family?

People often inherit XLH from their parents. However, the disease can also be the result of de novo mutations that occur for the first time in one family member. The genetic counselor will look at your family’s medical history, and may suggest genetic testing of other family members.

How will XLH affect my/my child’s life?

XLH can affect many aspects of your or your child’s life. Your genetic counselor can give you more guidance on things such as possible disabilities and life expectancy.

How might a positive test affect my having children?

If you or your partner has XLH, you are likely wondering if you can pass the disorder to your children. XLH is a genetic disorder inherited in an X-linked dominant manner. The risk of passing on the disease varies depending on who has the disease (the mother or father), and the gender of the child. A genetic counselor can help in calculating your risk.

Can diagnostic tests be done prior to or during pregnancy?

There are several options to check for XLH at different stages of fetal development. Preimplantation genetic diagnosis can be done on embryos created by in vitro fertilization. Prenatal testing can check the fetus for XLH early in a pregnancy. Your genetic counselor can explain options available to you, and their risks.

Last updated: Oct. 2, 2020

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XLH News Today is strictly a news and information website about the disease. It does not provide medical advice, diagnosis, or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.