Prenatal and Pre-implantation Genetic Diagnosis

Since BHD syndrome is inherited, this creates a further consideration for patients who are considering having children. Before you make any decision about prenatal diagnosis or pre-implantation diagnosis, we strongly suggest seeing a genetic counsellor for guidance and to properly discuss the health implications of such a test.

  • Prenatal Diagnosis (PND)

It may be possible to test for mutated genes during pregnancy and to find out if the unborn child has Birt-Hogg-Dubé syndrome. 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 syndrome, 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 Birt-Hogg-Dubé syndrome from the affected parent.

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 counsellor if you would like to locate a lab that does prenatal testing.

If it is determined during pregnancy that a child has BHD syndrome, it is not currently possible to know or predict which symptom or combination of symptoms the child will have. Of the more common BHD manifestations, pneumothorax is the only symptom known to occur in children. Cases of pneumothorax have been reported in BHD syndrome patients as young as seven and sixteen years of age (Bessis et al., 2006; Gunji et al., 2007). Skin lesions and kidney cancer have not been identified during childhood. Currently the first recommended screening age of people at risk of Birt-Hogg-Dubé syndrome is 20.

  • Pre-implantation Genetic Diagnosis (PGD)

PGD is a procedure that takes place before a pregnancy. It can be an alternative to PND, although it is not as widely available. Different countries have different legal positions on PGD, and the ethics of this procedure have been widely debated. Seeing a geneticist or a genetic counsellor before choosing PGD may be required and is certainly recommended.

Pre-implantation 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 who know that one of them has a hereditary or genetic condition choose to have embryos tested for mutations before they are implanted in the uterus.

We understand that the Genesis Genetics Institute has successfully conducted PGD for BHD syndrome in the US and the UK.  The Genesis Genetics Institute has facilities worldwide.

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