The purpose of the project is to obtain skin and adipose tissue samples from patients with ALS to develop new diagnostic and prognostic markers of the disease. These samples will be obtained when percutaneous endoscopic gastrostomy (PEG) is performed as part of their standard of care. Skin and adipose tissue samples will also be obtained from disease control subjects who require a PEG as part of their standard of care.

Subjects who are undergoing a percutaneous endoscopic gastrostomy (PEG) tube insertion as part of their standard of care will be asked if a skin and adipose sample may be collected for research during the procedure. After a participant has signed the informed consent, the sub-investigator from the Department of Gastroenterology will collect a skin and adipose sample during the procedure. Individuals with a diagnosis of definite ALS and disease controls (i.e. stroke, head and neck cancer, spinal cord injury, etc.) will be included in this study.

The coded skin and adipose sample will be taken to the Carolinas Neuromuscular/ALS Research Laboratory in the Cannon Research Center for processing. The skin and adipose will be separated from each other and divided into halves. Each half of skin and adipose will be submerged in preservative and either shipped to ALS-TDI or retained at -80°C in the Carolinas Neuromuscular/ALS Research Laboratory. The research staff at the Carolinas Neuromuscular/ALS-MDA Center will be responsible for shipping the sample to the ALS-TDI for either RNA isolation using the Qiagen RNAEasy kit (Qiagen) or for purification of protein. Subsequently, gene expression profiling on Affymetrix Genechips or Mass Spec based proteomics on a Thermo Orbitrap LC-MS/MS instrument will be performed, respectively. The discovery effort (if all participants are working at capacity) should not take more than 12 months.

In addition to the above procedures, a member of the study team will review the medical chart to obtain additional information on the participant's medical and family history. For ALS patients, past ALSFRS-R scores or FVC scores will be provided to the "ALS-TDI Skin and Adipose Biomarker Study" to enhance the usefulness of the information for research.

Samples will not be stored with any patient identifiers. Samples will be retained and continued to be studied as new techniques become available. Data from the study may be published in scientific journals. Publications will not include any patient identifiers.

Inclusion Criteria:

• for ALS patients, subjects must be diagnosed with definite ALS according to the El Escorial Criteria (EEC)
• all subjects must be diagnosed with a condition requiring PEG (percutaneous endoscopic gastrostomy) tube insertion
• subjects must be older than 18 years of age

Exclusion Criteria:

• children 18 years old and younger

Patients at the Carolinas Neuromuscular/ALS-MDA Center and patients at Carolinas Medical Center.