ALS is difficult to diagnose because the initial symptoms can be very similar to other diseases. A neurologist will typically diagnose ALS through a process of reviewing symptoms and eliminating other possible diseases.

Any or all of these tests may be used to help diagnose ALS:

  • Blood and urine studies
  • Electrodiagnostic tests including electomyography (EMG) and nerve conduction velocity (NCV)
  • Magnetic resonance imaging (MRI)
  • Muscle and nerve function tests

Genetic testing for ALS

Genetic Testing for ALS Facts

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Diagnosing ALS does not involve a genetic test. However, someone with a family history of ALS may be interested in a genetic test to identify if they inherited the gene mutation that would put them at a higher risk of developing the disease. The genetic test involves a blood sample from which DNA is removed to test for one of the known gene mutations.

Deciding whether to take the test is a challenging and personal choice. Knowing that one has a gene mutation linked to the development of ALS can be difficult information to live with since to date, there are no effective treatments for ALS and no cure. A clinician at one of the Canadian ALS clinics will be able to provide you more information or direct you to a genetic counselor to assist in your decision process.

It is important to remember that people who have inherited the gene mutation that increases the risk of ALS do not always go on to develop the disease.

Children of those with sporadic ALS have no greater likelihood of developing ALS than the rest of the population.


Sources:                                                                                                                                                                  http://als.org/index.php?page=about_als&sub=diagnose                                                                           http://als.org/index.php?page=about_als&sub=testing                                                                                          Current as of November 14, 2016