Hereditary sensory neuropathy, type II also known as HSN2 is a region of a parent protein which in humans is encoded by the WNK1 gene.[1][2] It is a transcript variant of the WNK1 gene that is selectively expressed in nervous system tissues, and during development. Mutations in this exon of the WNK1 gene have been identified as causative in genetic neuropathy syndromes, and in inherited pain insensitivity.