In support of the acquired irreversible Piezo2 channelopathy theory of ALS, the intrafusal group Ia afferents are highly represented by Kv1.1 and Kv1.2 ion channels, substantiating their role in proprioception, and they are suggested to contribute to their dynamic firing properties [57]. This evidence concerns the gene KCNA1 and amyotrophic lateral sclerosis.