Congenital anosmia is a condition that begins at birth where the individuals are unable to smell. This condition is very rare and can occur on its own or be a symptom of another condition. Congenital anosmia has been associated with Kallman syndrome and Klinefelter syndrome. Isolated congenital anosmia is thought to be caused by errors in the development of the olfactory system and might be a mutation of a gene on chromosome 18. Unfortunately, there is no known cure or treatment for this condition.