What is the primary composition of Howell-Jolly bodies?

The primary composition of Howell-Jolly bodies is DNA. These are small, round inclusions observed within red blood cells, typically seen in conditions where the spleen is absent or not functioning properly. Howell-Jolly bodies are remnants of nuclear material, specifically fragments of DNA that are not properly removed during the maturation of red blood cells in the bone marrow.

In a normal physiological context, the spleen plays a crucial role in filtering out these nuclear remnants. Therefore, their presence indicates a defect in normal erythrocyte maturation or a loss of splenic function, thus serving as an important diagnostic marker in hematological evaluation. Understanding this composition can help in interpreting laboratory findings related to conditions such as splenic dysfunction or post-splenectomy status.