A rare condition known as chimerism can lead to individuals possessing two distinct sets of DNA within their own bodies, often without their knowledge. This can cause confusing results in situations like paternity tests, where a mother might initially appear unrelated to her child.

• Chimerism involves a single organism composed of two or more genetically distinct populations of cells.
• Founder and Principal Pathologist Dr. Ahmed Kalebi at Dr. Kalebi Labs (DKL) explained that chimerism is generally harmless and does not affect personality or behavior.
• Types of chimerism include tetragametic (two fertilized eggs merging), microchimerism (cell exchange between mother and fetus), and artificial chimerism (due to medical procedures like transfusions or transplants).
• While chimerism often goes unnoticed, its detection is significant for medical diagnoses, particularly in organ transplants and blood typing, with advanced technologies like deep sequencing and multi-tissue testing expected to improve its detection.