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  • Affected: A person who has the condition in question.
  • Amino acid: The building block of proteins. Amino acids are determined by the sequence of bases found in a person's genetic code (DNA). In general, if a mutation in a gene does not cause an amino acid to change, it is unlikely that it is the cause of a person's condition.
  • Autosomes/autosomal: One of the first 22 pairs of chromosomes (all excepting the sex chromosomes - X and Y). If a person has a condition that is found on an autosome, there is an equal chance of it affecting males and females, and an equal chance of passing on the condition, no matter the gender of the person affected.
  • Axon: The central part of a nerve through which signals are sent.
  • Axonal: Due to the axon.