The present invention is based on the discovery and
cloning of the human small conductance
calcium activated
potassium channel type 3 (hKCa3 / KCNN3)
gene, which is expressed in neuronal cells,
skeletal muscle, heart, and lymphocytes. Alterations in the hKCa3 / KCNN3
gene or its
protein product may enhance susceptibility to
schizophrenia and / or bipolar disorder. hKCa3 / KCNN3 may be involved in neuropsychiatric, neurological, neuromuscular, and immunological disorders. Substantially purified hKCa3 / KCNN3 polypeptides and polynucleotides are provided. Antibodies which bind to hKCa3 / KCNN3 polypeptides are also disclosed. A method for identifying a compound which affects hKCa3 / KCNN3
polynucleotide or polypeptide is provided. A method for diagnosis and determining the prognosis and
treatment regimen of a subject having or at risk of having a hKCa3 / KCNN3-associated disorder is also provided. A method of treating a subject having or at risk of having an hKCa3 / KCNN3-associated disorder by administering a therapeutically effective amount of a
polynucleotide encoding SEQ ID NO:2 is also provided. A formulation for administration of hKCa3 / KCNN3 to a patient of a therapeutically effective amount of hKCa3 / KCNN3 polypeptide is provided. Kits useful for detecting the presence of hKCa3 / KCNN3 polypeptide or
polynucleotide in a sample from a subject having a hKCa3 / KCNN3-associated disorder are provided. Transgenic nonhuman animals having a
transgene encoding hKCa3 / KCNN3 are also described.