Microgenia is the medical term for an unusually small or deformed chin.
The contrasting condition, an enlarged chin, is called "macrogenia".
There are seven different chin deformities: Class I: Macrogenia (chin excess) Class II: Microgenia (chin deficiency) Class III: Combined excesses and deficiencies Class IV: Asymmetric deformity Class V: Witch's chin Class VI: Pseudomacrogenia Class VII: Pseudoretrogenia
Class II microgenia is the most commonly encountered chin deformity, followed by class II macrogenia.
Causes Can occur in anyone, but is often a sign of Down syndrome. Microchinia mentioned among other characteristics of Down's Syndrome about halfway down the page.
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