The complete absence at birth of an organ or bodily component, caused by failure of development in the embryo.
Agenesis means incomplete development, or the failure of any part or organ of the body to develop normally.
n. absence of an organ, usually due to total failure of its development in the embryo. Dental agenesis (also known as *hypodontia) is the most common developmental anomaly in humans and may be caused by genetic defects in codes for transcription factors, proteins, and fibroblast growth factors.
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