Panel Composition and Demographics
This panel contains 5 µg DNA from 92 unique and unrelated White individuals with sporadic amyotrophic lateral sclerosis (ALS). These include 57 males and 35 females from North America. The age of ALS onset ranges from 40 years to 88 years. This was defined as when symptom(s) of ALS were first noted (including at least one: lower motor neuron signs (LMN) including weakness, atrophy, fasciculations; upper motor neuron (UMN) signs including spasticity, pathologic spread of reflexes, clonus, etc). NDPT103 replaces NPDT029, and contains the same samples except: ND12936 (no longer available) and ND10641 (no longer available) are removed and are replaced by ND10143 and ND09553. ND11897 and ND10000 each appear twice on the panel as internal controls. Wells F07 and H04 are empty for addition of a laboratory control.

Panel Design The concentration of each DNA sample to be plated is normalized and then this concentration is verified. Two samples are repeated to assess data reproducibility, and sample placement has been optimized to reduce possible errors in sample identity during the genotyping process. Two wells remain empty for investigator control samples.

Diagnostic and Clinical Features The phenotypic details of any single subject can be viewed through the list of panel members by clicking on the individual ID number. For subject inclusion, complete NINDS Repository Clinical Data Elements (CDEs) were required. Furthermore, only subjects who (a) had no family history of ALS (i.e. sporadic ALS) and (b) met the El Escorial criteria for definite (n=66) and probable (n=26). (Brooks BR. El Escorial World Federation of Neurology criteria for the diagnosis of amyotrophic lateral sclerosis. J Neurol Sci 1994;124 Suppl:96-107 & Miller RG, Munsat TL, Swash M, Brooks BR, for the World Federation of Neurology Committee on Research. Consensus guidelines for the design and implementation of clinical trials in ALS. J Neurol Sci.1999;169:2-12). None of the subjects had exclusionary features. All subjects had progressive spread of signs characteristic of ALS, together with the absence of (1) electrophysiological evidence of other disease processes that might explain the signs of LMN and/or UMN degeneration, and (2) neuro-imaging evidence of other disease processes that might explain the observed clinical and electrophysiological signs. All samples and data were collected with informed consent under local IRB approved protocols.

Family history All subjects were queried regarding family history of ALS, parkinsonism, dementia, Alzheimer's disease, and other neurological dysfunction. Only subjects without a reported family history of ALS were included on this panel.