This ENU-induced mutation was isolated in a screen at the University of Pittsburgh. The molecular lesion is a T to C substitution at coding nucleotide 13169 in exon 76 of the cDNA (c.13169T>C, NM_133365). This changes the leucine residue to proline at position 4390 of the encoded protein (p.L4390P). (J:175213) Additional incidental mutations were detected in sequencing for the causative mutation, Dnah5b2b002Clo, and may be present in stocks carrying this mutation.