Inclusion Criteria:

c9ALS Patients

1. c9ALS proband as defined in Core B., blood relative of c9ALS proband identified through Core B to have c9ALS or suspected c9FTD, or patients who have already had DNA testing through a clinical laboratory confirming the presence of the c9ORF72 repeat expansion. This definition includes a diagnosis of El Escorial clinically definite, probable, possible or suspected ALS, allowing for cognitive and behavioral impairment and/or extrapyramidal signs corresponding to the range of phenotypes reported in c9FTD/ALS
2. ≥18 years of age
3. Willing and able to provide written informed consent, or assent, if physically unable to sign the consent form.
4. Willing and able to comply with scheduled protocol related visits as per protocol.
5. Speak English as a primary language because some components of the neuropsychological battery are not validated in languages other than English.
6. Patients will be eligible to participate whether or not they choose to take riluzole.
7. Able to comply with standard phlebotomy procedures

c9(-)ALS Patients

1. c9(-)ALS patient as defined in Core B., or blood relative of c9(-)ALS patient identified through Core B to have ALS (or suspected FTD). However, c9(-)ALS patients will meet diagnostic criteria for El Escorial clinically definite, probable, or probable lab-supported ALS, allowing for cognitive and behavioral impairment attributable to the neurodegenerative disorder.  These narrower diagnostic criteria than those applied for c9ALS patients are intended to help insure a diagnosis of classical ALS and increase homogeneity in the c9(-)ALS cohort.
2. ≥18 years of age
3. Willing and able to provide written informed consent, or assent, if physically unable to sign the consent form.
4. Willing and able to comply with scheduled protocol related visits as per protocol.
5. Speak English as a primary language because some components of the neuropsychological battery are not validated in languages other than English.
6. Patients will be eligible to participate whether or not they choose to take riluzole.
7. Able to comply with standard phlebotomy procedures.

ALS Family members in c9ALS Pedigree Cohort and c9(-)ALS Pedigree Cohort

c9(+)Relatives and c9(-)Relatives and ALS Relatives

1. c9(+)Relative, c9(-)Relative or ALS Relativeas defined in Core B
2. ≥18 years of age
3. Willing and able to provide written informed consent.
4. Willing and able to comply with scheduled protocol related visits as per protocol.
5. Speak English as a primary language because some components of the neuropsychological battery are not validated in languages other than English.
6. Able to comply with standard phlebotomy procedures.

Exclusion Criteria:

c9ALS Cohort and c9(-)ALS Cohort

1. History of medical disorders that leave in doubt the diagnosis of ALS.
2. History of superimposed medical conditions that could impact cognitive function such as substance abuse, major head trauma or stroke.
3. History of clinically significant active or unstable medical condition or procedure (i.e., seizure disorder; unstable cardiac condition, stroke, major trauma, or major surgery) within the last 30 days.
4. If physically unable to sign the consent form, lack of an available representative to sign the consent on behalf of the patient.
5. Receiving experimental treatment that could impact interpretation of study outcome measures; if potential impact of the experimental intervention on study data is uncertain, the subject may be enrolled and the potential effects of study intervention will be considered in the outcome analysis. This approach may require modification depending on developments in ALS therapy and experimental ALS treatment.

ALS Family members in c9ALS Pedigree Cohort and c9(-)ALS Pedigree Cohort

c9(+)Relatives and c9(-)Relatives and ALS Relatives

1. Development since of 1) motor signs on physical examination supporting a diagnosis of ALS or Parkinson disease or 2) ALS CBS cognitive score <15, behavioral score <34, and/or MoCA score <26. Presence of any of these findings would result in further evaluation and possible reclassification of the subject for purposes of clinical data collection.
2. History of superimposed medical conditions that could impact cognitive function such as substance abuse, major head trauma or stroke.
3. History of clinically significant active or unstable medical condition or procedure (i.e., seizure disorder; unstable cardiac condition, stroke, major trauma, or major surgery) within the last 30 days.