Definition: Hemerobius is a term used in the field of genetics to describe individuals that lack hemoglobin, which is an essential protein found in red blood cells. This condition can result from genetic mutations or inborn errors and affects the oxygen-carrying capacity of red blood cells. Hemerobies are typically associated with genetic disorders such as sickle cell disease, where the hemoglobin molecule becomes distorted during maturation, leading to a decrease in oxygen transport efficiency.