How is Fabry disease inherited?
Fabry disease is passed through families in an X-linked inheritance pattern, meaning the GLA gene that causes Fabry disease is located on the X-chromosome. Women have two copies of the X-chromosome (XX) and men have one copy of the X-chromosome and one copy of a Y-chromosome (XY). If men inherit an X chromosome containing the non-working GLA gene, they are unable to produce alpha-Gal enzyme. Without alpha-Gal, GL-3 builds up in the body and causes the symptoms and health problems of Fabry disease. On the other hand, if women inherit an X chromosome with a nonworking GLA gene, they have a second X-chromosome with a working GLA gene that can produce some alpha-Gal enzyme. In the past, it was believed that women who were "carriers" would not have Fabry related health problems because they had a normal second copy of the gene. However, women are not just carriers and they can have Fabry related health problems. Fabry disease is unique, as most X-linked disorders affect males primarily. It is important to speak to your physician about all your signs and symptoms and not rule out Fabry disease if you are a female.
The chance for children to have Fabry disease depends on whether the father or the mother has Fabry disease and the X-chromosome with the non-working GLA gene. If a man's X-chromosome contains the nonworking GLA gene, he will pass it on to all of his daughters and none of his sons. If one of a women's X-chromosomes contains the nonworking GLA gene, she will have a 50% chance with each pregnancy of passing it on to both her daughters and sons. Both males and females can have Fabry disease.
To find a genetic professional near you who can discuss the chance for someone with Fabry disease to have a child with Fabry disease or discuss genetic testing options consult a genetic counselor. Genetic counselors can be found on the National Society of Genetic Counselors website: http://www.aboutgeneticcounselors.com/
- Laney, D., Bennett R.L., Clarke V., Fox, A., Hopkin, J., Johnson, J., et al. (2013). Fabry Disease Practice Guidelines: Recommendations of the National Society of Genetic Counselors. Journal of Genetic Counseling, 22, 555-564.
- National Fabry Disease Foundation. (n.d.). Retrieved from http://www.fabrydisease.org.
More Inheritance Content
I have Fabry disease. Will my children have it?
Fabry disease is inherited in an X-linked pattern. Both men and women can experience symptoms of the disease.
The chance for a child to inherit Fabry disease depends on whether the father or the mother has Fabry disease. If a man has Fabry disease, then his only X-chromosome contains the nonworking GLA gene and he will pass it on to all of his daughters and none of his sons. If a woman has Fabry disease, only one of her X-chromosomes contains the nonworking GLA gene. This means she will have a 50% chance with each pregnancy of passing it on to both her daughters and sons. Both males and females can have Fabry disease.
If a child is the first in the family to be diagnosed with Fabry disease, it was likely inherited from one of their parents who has not yet been diagnoses, although spontaneous (de novo) gene changes that occur for the first time in that child are possible as well. Each parent of a child with Fabry disease should be tested for the same known mutation in the GLA gene.
If Fabry disease runs in a family, genetic testing is available to determine who else in the family is affected. In fact, there are several free testing programs for Fabry disease. For more information about testing, you should speak with your healthcare provider. A genetic counselor can also help determine and individual's risk of having Fabry disease based on a detailed family and medical history as well as discuss and organize testing. For individuals who live in the United States, genetic counselors in your area can be found on the National Society of Genetic Counselors website: http://www.aboutgeneticcounselors.com/
- Mehta A, Hughes DA. Fabry Disease. 2002 Aug 5 [Updated 2017 Jan 5]. In: Adam MP, Ardinger HH, Pagon RA, et al., editors. GeneReviews® [Internet]. Seattle (WA): University of Washington, Seattle; 1993-2019. Available from: https://www.ncbi.nlm.nih.gov/books/NBK1292/
- Fabry disease revisited: Management and treatment recommendations for adult patients. Ortiz A, Germain DP, Desnick RJ, Politei J, Mauer M, Burlina A, Eng C, Hopkin RJ, Laney D, Linhart A, Waldek S, Wallace E, Weidemann F, Wilcox WR. Mol Genet Metab. 2018 Apr;123(4):416-427. doi: 10.1016/j.ymgme.2018.02.014. Epub 2018 Feb 28. Review. https://www.sciencedirect.com/science/article/pii/S1096719217307680?via%3Dihub Retrieved 12DEC19.
- Laney DA, Bennett RL, Clarke V, Fox A, Hopkin RJ, Johnson J, O'Rourke E, Sims K, Walter G Fabry disease practice guidelines: recommendations of the National Society of Genetic Counselors. J Genet Couns. 2013 Oct;22(5):555-64. http://www.ncbi.nlm.nih.gov/pubmed/23860966