Low set ears (Lse), a new mutation of the house mouse.

A new dominant mutation, low set ears (Lse), in the mouse may be indicative of a mammalian branchial arch syndrome. This developmental anomaly of the external ear is accompanied by eye defects, retarded growth and shortened lifespan. The ear defect can be identified in 13-day embryos. Further studies will determine the effects of the Lse gene on other systems.