Gene Test

Who should be tested for BHD?

If anyone in your family has the Birt-Hogg-Dubé syndrome, you could also have it. Anyone who is a parent, child or sibling (a first degree relative) of someone with BHD is at risk. Anyone who is a second degree relative of someone with BHD is also at risk; this includes grandparents, grandchildren, aunts, uncles and cousins.

If you think you may have BHD, we urge you to discuss this with a doctor. This could be your primary care physician, or a specialist. Your doctor can help you arrange to be tested for the altered BHD gene. The test is easy and painless, and in most cases is covered by insurance.

We believe that it is important to be tested because once you know you have BHD, you will know to monitor your health for the rest of your life. You’ll be able to react quickly and appropriately if you need medical attention. Since having the Birt-Hogg-Dubé syndrome does put you at risk for kidney tumors, it is important that you be checked regularly. This should enable you to manage the symptoms and to go on with your life. You may want to read our sections on Insurance and Genetic Counseling before ordering your test.

The only way to know if you have BHD is by having the gene test. If you are at risk for BHD and do not have any skin symptoms, this does not mean you don’t have BHD. If you have never had a spontaneous pneumothorax or any kidney tumors, you could still have BHD, and your children may have it.

Once the first person in a family has been tested and the family gene mutation has been identified, other family members need only be tested for that particular mutation. This is less expensive than the first test.

The BHD gene has been identified, so technically any qualified lab can check your DNA to see if you have an alteration in this gene. However, not all labs that offer genetic testing currently test for the Birt-Hogg-Dubé gene mutation. We include contact information for two labs in the U.S. at the bottom of this page.

For the DNA test, you can go to a doctor to have blood drawn, and your doctor can arrange to have it sent for testing. When blood is used, time is of the essence because the blood has to arrive at the lab in a specified time frame.

Alternatively, you can order a kit with a buccal swab from Gene Dx (think of a sponge lollipop= that’s what this looks like). You swirl it against your cheek, put it in the container you received with the kit, and send it in for testing.

You will get a result telling you if you have such the Birt-Hogg-Dubé gene alteration, and what your particular mutation is. If you have BHD, the results will be positive.

This is a fairly costly procedure; it is currently (2008) over $1600 most places if you pay for it yourself.

Once a family member has been diagnosed with BHD, it is possible for other family members to be tested for that person specific mutation only, in order to confirm the presence or absence of BHD. A separate mutation test is less costly than a gene test; the price for this is currently (2008) several hundred dollars.

The results will not be sent directly to you, even if you request that this happen. They will be sent to your doctor.

Steps to get tested for BHD in the USA:

Blood test

  1. Contact your doctor. (This can be your primary care physician, or a specialist who is helping you with your BHD symptoms.)
  2. Ask your doctor to arrange to draw 5ml blood (one small tube). The information you got from the lab will have details about how to have the blood shipped overnight, and your doctor should be familiar with this type of procedure.

If you would like more specific instructions about how to do this, the lab can fax them to you, either to your home or to the doctor´s office.

The instructions will include the lab protocol, which contains sample requirements, shipping instructions, and the paperwork needed to order the test.

Buccal (cheek swab)

  1. Contact the lab to see if they will do a buccal swab test. Ask them to send you the test kit and information.
  2. Swab your cheek (imagine swiping the inside of your cheek with a cotton swab.) Put the swab in the container and mail it to the lab.

A buccal swab test does not have to pass the same customs regulations that fresh blood does.

Steps to get tested for BHD in the UK:

A BHD diagnosis will involve referral from your GP to a Medical Genetics Clinic and is free on the NHS. Specialist medical health care professionals will organise a genetic diagnosis for you, and will ask for information regarding your family history and possible routes of surveillance for yourself and other family members. Molecular diagnosis of BHD Syndrome will involve providing a blood sample which is then analysed by your regional molecular diagnostic laboratory.

Confirmation that you have BHD Syndrome can lead to lots of questions and it is natural to have concerns after a positive diagnosis.

You will be able to discuss these concerns with either your GP, or with the clinical geneticists who handled your diagnosis – whoever you feel more comfortable with.

Clinical geneticists will probably not be specialists in the field of BHD Syndrome, but they will have been trained to deal with the issues arising from a positive diagnosis of a genetic disease such as BHD Syndrome.

They can help individuals explore what it means to have BHD syndrome on a personal level but also assist in discussing the wider implications of a positive diagnosis of a genetic disease. This may include family planning issues or help in identifying living family members who are at risk of having BHD Syndrome.

Prenatal and Preimplantation Genetic Diagnosis

Before you make any decision about prenatal diagnosis or preimplantation diagnosis, we strongly suggest seeing a genetic counselor for guidance and to properly discuss the health implications of such a test.

Prenatal Diagnosis (PND)

It may possible to test for mutated genes during pregnancy and to find out if the child has the Birt-Hogg-Dubé syndrome before the child is actually born. If you are researching this option, you may see it called prenatal testing or prenatal genetic diagnosis as well.

If one of the parents has BHD, then every child they have has a 50 % chance of also having BHD. By testing before birth, parents would know if the child has inherited the Birt-Hogg-Dubé syndrome from the affected parent.

Of the more common manifestations of BHD – skin lesions and kidney cancer  have not been found in children during childhood, but cases of pneumothorax have been reported in BHD syndrome patients as young as seven and sixteen years. Should it be determined during pregnancy that a child has BHD, it is not currently possible to know or predict which symptom or combination of symptoms a child with BHD will have. Currently the first recommended screening of people who have an identified case of Birt-Hogg-Dubé would start at age 21.

In most cases, the test can be done at 10-12 weeks into the pregnancy by chorionic villous sampling (CVS). Another alternative is amniocentesis, which in most cases is done at 15-18 weeks.

Prenatal diagnosis is not universally available and you should consult your doctor or genetic counselor if you would like to locate a lab that does prenatal testing.

Your health insurance may or may not cover this procedure; it is always a good idea to check ahead of time.

Preimplantation Genetic Diagnosis (PGD)

PGD is a procedure that takes place before a pregnancy. It can be an alternative to prenatal diagnosis (PND) and is not as widely available. Different countries have different legal positions on PDG, and the ethics of this procedure have been widely debated. Seeing a geneticist or a genetic counselor before choosing a Preimplantation Genetic Diagnosis may be required and is certainly recommended.

Preimplantation Genetic Diagnosis may be considered as a step in the in vitro fertilization (IVF) process. This procedure is not standard for all people who are considering IVF, but would be used only if the parents wished to know if an embryo had a genetic mutation or not. Some couples that know one of them has a hereditary or genetic condition choose to have embryos tested for mutations before they are implanted in the uterus.

Have any outsanding questions or issues you’d like to discuss? Why not post on our forum for some advice?

Sources

www.BHDsyndrome.or is not responsible for the content of third party websites