A new mutant with shivering, Hula dance Sendai (tentatively named hus gene), was found in the IVCE strain. A congenic strain, C57BL/6JJcl-hus, was established by the cross-intercross method using IVCE-hus as the donor strain and C57BL/6JJcl as the recipient. No significant differences were observed in the age of the onset of shivering and life span between B6-hus and IVCE-hus mice. Genetic analyses demonstrated that this mutation is governed by an autosomal recessive gene (Mbphus) and is an allele of the Mbpshi gene (Chr. 18).