The intronless STH gene lies between exons 9 and 10 of the tau gene, which is implicated in a number of neurodegenerative disorders. It encodes a 128 residue protein with no clear homologs, and mimics the expresison patterns of tau. Though a polymorphism (Q7R) appears significant, data does not clearly show thus far whether or not this phenotype provides a useful marker for Alzheimer’s or other forms of neurodegenerative disease.