Other HOXA13 mutations result in the production of an abnormally short, nonfunctional version of the HOXA13 protein or change single amino acids in the protein. Mutations that substitute one amino acid for another amino acid may change the way the HOXA13 protein is folded. The altered protein may or may not function or bind to DNA normally. Mutations that result in an altered but functional HOXA13 protein may cause more severe signs and symptoms of hand-foot-genital syndrome than mutations that lead to a nonfunctional version of this protein.