OMA is not a precursor to ataxia but a person can have both. The pediatric geneticist tested our daughter for elevated levels of alphafetoproteins (a blood test)to see if she might be predisposed for ataxia. Her test came back normal and the geneticist that we could 'rest easy' that she would not develop ataxia. The doctor also said ataxia is typically evident within the first 3 years.