Genetic Testing & Counseling
Genetic testing can be used to confirm or reject a suspected diagnosis,
to test for a disease prior to the appearance of symptoms, or plan for the
future. The decision to pursue genetic testing can be overwhelming but there
are resources which can assist you in making the best decision. A meeting
with a genetic counselor can aid you in your decision by bridging the gap
between complex scientific information and personal concerns surrounding
At the initial appointment, the genetic counselor will ask you to provide
your personal and family medical history, to develop an understanding of
your genetic risk. Prior to the first appointment, it is useful to collect
as much information regarding your family history of muscular dystrophy,
including medical records or previous genetic test results from affected
family members. During the first appointment, the genetic counselor will
provide you with information regarding the inheritance pattern for the disorder,
the genetic testing process and the possible test outcomes. Recommendations
for additional services such as medical treatment, counseling or support
groups can also be provided. A genetic counselor or physician will not decide
if you should pursue genetic testing, they will only provide you with the
knowledge to make an informed decision.
Genetic consultations can be obtained through hospitals, clinics and some
genetic testing labs. There are counselors who specialize in genetic counseling
for individuals and families with muscular dystrophies.
Genetic tests are ordered by a primary care physician, specialist or genetic
counselor. A blood sample will be taken and sent to a clinical laboratory
which specializes in genetic testing for patient medical care. The results
take approximately 2-6 weeks to arrive and will be sent directly to the
healthcare provider that ordered the test. A genetic counselor will schedule
an additional appointment to go over your test results and offer suggestions
for follow up visits and additional treatment if necessary. Genetic tests
can be performed in research laboratories, although these results are often
not shared with the patient and are used to learn more about a disease or
develop new clinical tests.
Additional Testing Options
As we develop an increased understanding of the genetic mechanisms and
causes of muscular dystrophy, stored DNA samples can be a valuable resource
to you and your family. DNA banking is the process in which DNA is extracted
from white blood cells and stored indefinitely by storing the DNA at extremely
low temperature. DNA can also be extracted from the cells that line the
cheeks (buccal cells) which are collected using a cotton swab. The DNA is
stored at a secure and environmentally controlled facility that the patient
or family has chosen. The can be removed from the facility at any point
by the individual who “owns” the DNA.
DNA banking is an option often utilized by individuals who may not want
to undergo genetic testing, but would like to have a DNA sample available
for their children if needed in the future. A DNA sample from an affected
individual can increase the accuracy of DNA testing in other family members.
The DNA will also be available if there is a change in the diagnostic criteria
or newer tests become available. Additionally, previously collected DNA
is more convenient for future DNA testing then having to extract a new sample.