Mutation (deletion of 19bp and insertion of 1bp) within the first exon of promL.
20bp in the first coding exon of promL are deleted and replaced with a "C" leading to a net 19bp deletion and a frameshift mutation.
C
promLΔ19 adults survive longer (under starvation and normal feeding conditions) while they do not exhibit any significant morphological or developmental defects (such as body size and weight) when compared to controls.