By Keith S. Wexler, MBA, Maternal Fetal Medicine, Prenatal Diagnosis and Biotech Consultant
Paul Wexler, M.D., F.A.C.O.G., Medical Director, GENASSIST, Inc.
Clinical Professor, Department of OB/GYN, University of Colorado Health Sciences Center
Clinical Professor, Division of Genetics/Dept. of Pediatrics, Univ. of Colorado/The Children’s Hospital
We received the following cold-email last week and it helps illustrate the excitement and confusion that all of the wonderful genetic tests that are available to consumers are creating and the misunderstanding of the pros and cons of seeking such testing:
“I am interested in more information regarding genetic screening for Fanconi Anemia. My wife and I would like to rule out the potential of our daughter being a carrier by screening me for the gene.”
Our email response to the father was:
- Who in the family has Fanconi Anemia?
- What led you and your wife to request Fanconi Anemia testing?
- Are you of Ashkenazi ancestry? If yes, are you aware that there are Ashkenazi Jewish Inherited Disease panels that can help identify or rule-out over 40 diseases often for the same cost as trying to rule out a single disease?
- Even if you are not a “carrier” do you understand that does Not rule out your daughter being a carrier, since your daughter’s mother can be a carrier?
To date, we have not received a response to our questions.
Fanconi Anemia is has a carrier frequency of (1 in 89) and affects up to (1 in 31,000) pregnancies. It is more common in individuals of Ashkenazi Jewish heritage.
Very rarely, Fanconi Anemia can be inherited in a Sex (X-Linked) manner. 50% of male or female children from a carrier female (mother) can inherit the gene. Mutations in up to 15 genes have been described as involved in the disease.
Fanconi Anemia: Autosomal recessive inheritance (25% if both parents are gene carriers) has been described.
Fanconi Anemia is characterized by abnormal skin pigmentation, abnormal forearms, abnormal or absent thumbs and urinary tract abnormalities. Heart, intestinal and other skeletal abnormalities may be present. Bone marrow failure usually occurs in early childhood and patients with this disease are at an increased risk for malignancies.
*The Ashkenazi Jewish Screen is available in a variety of Panels:
- Basic Panel – 3 Diseases
- Expanded Panel – 8 Diseases
- *Full Panel – 18 Diseases – (One company is running a 3 part Ashkenazi panel that screen for over 39 diseases)
*The Full Panel is now also part of many Microarray Panels that can test for over 100 diseases.
The Jewish population in the United States as of 2012 was 6,543,820 making up 2.1% of the entire U.S. population (1).
The Ashkenazi Jewish Inherited Disease Panel was created to help screen for specific ethnic inherited diseases. Preconceptional testing is suggested to help identify or rule-out the parents as being carriers.
(1) US Census Bureau, Statistical Abstract of the United States, 2012
We discuss “Ethnic Screening” as possibly being misleading since many individuals do not know their true ethnic background or have incorrect information about their heritage:
The dilemma for healthcare providers, especially genetic counselors, that are being called upon to help patients navigate the myriad of genetic test(s), microdeletion, microarray panels is addressing the when and why the patient is requesting the specific test(s) he/she is requesting.Although on the surface, the above email inquiry seems simple, “I want to be tested for Fanconi Anemia…to rule out the potential of our daughter being a carrier by screening me for the gene” really does not make medical sense.
Even if the mother and father are Fanconi Anemia negative, that does not mean that the daughter does not have Fanconi Anemia.
If the father wants to rule out whether or not his daughter is a carrier or not of a specific gene, then logic would dictate that he should test the daughter.
This raises a huge ethical dilemma (Pandora’s box) for the parents depending upon which state or country the family lives in.
In the United States, there are many states that will not allow a parent to test their “unaffected” child to see if he or she is a carrier of a disease until the child becomes an adult. If the disease that the parent is concerned about (i.e. Alzheimer’s, Parkinson’s etc.) will not affect the child until he or she is an adult, many states believe that since the test result may affect that child’s “quality of life”, and it should be the child’s decision and not the parents decision to get tested.
How does a parent weight the benefits of “protecting” his or her child from harm (i.e. Fanconi Anemia) versus the possible damage of finding out information that might or might not affect their child in his or her lifetime?