3])
Scientists have identified multiple genes associated with ALS, including:
* C9orf72
* SOD1
* FUS
* TARDBP
Research continues into how genetics, cellular processes, and environmental factors contribute to the disease.
## How Is ALS Diagnosed?
There is no single simple blood test that confirms ALS.
Diagnosis generally involves:
* Detailed neurological examination
* Medical history
* Electromyography (EMG)
* Nerve-conduction studies
* Blood tests
* Imaging when appropriate
* Other testing to exclude similar conditions
ALS can be difficult to diagnose early because several neurological and muscular diseases can mimic its symptoms. ([Mayo Clinic][2])
## Conditions That Can Mimic ALS
Progressive weakness, twitching, or speech problems can occur with many conditions other than ALS.
Doctors may consider possibilities such as:
* Peripheral neuropathy
* Cervical spine problems
* Myasthenia gravis
* Multiple sclerosis
* Vitamin deficiencies
* Thyroid disorders
* Certain muscular diseases
* Other motor-neuron disorders
This is why searching symptoms online cannot provide a reliable diagnosis.
## When Should You See a Doctor?
Arrange medical evaluation if
