Aberrant elemental composition of otoconia in the dancer mouse mutant with a semidominant gene causing a morphogenetic type of inner ear defect

Abstract

The elemental composition of otoconia from Jerker and Dancer mouse mutants was analysed in both maculae. A normal elemental content was found in otoconia from Jerker mutants, whereas in the Dancer mutant a large number of otoconia from both maculae contained very high concentrations of phosphorus. In these otoconia, the phosphorus calcium ratio was approximately 1:8, in Jerker (and normal) otoconia approximately 1:150-200. However, otoconia from Dancer mutants occurred with also a normal elemental composition. The increasing content of phosphorus in otoconia may possibly indicate an early onset of aging, i.e. corresponding to a phosphatization process as described in aging human otoconia.

Key Words:

• otoconia
• elemental composition
• microprobe
• Dancer
• Jerker
• mutant
• mouse
• pathology