The Hereditary Ataxias are a group of genetic disorders characterized by slowly progressive incoordination of gait and often associated with poor coordination of hands, speech, and eye movements. Current treatments for Hereditary Ataxias are mainly pharmacological, rehabilitative, or psychological treatments，while no effective treatment available. Stem Cell therapy is a novel and promising therapeutic strategy for Hereditary Ataxias treatment. In this study, the safety and efficacy of Human Umbilical Cord Mesenchymal Stem Cells transplantation will be evaluated in patients with Hereditary Ataxias.

This Study is designed to evaluate the the safety and efficacy of Human Umbilical Cord Mesenchymal Stem Cells transplantation in patients with Hereditary Ataxias.

Inclusion Criteria:

• Aged 16-65 years.
• Harding Diagnosis of SCAs, gene type confirmed.
• Candidates who did not receive any stem cell therapy in past 6months.
• sign the consent form and follow the clinic trail procedure.

Exclusion Criteria:

• Cardiac insufficiency; Renal insufficiency; hepatic insufficiency; Total bilirubin higher than 1.5 times of upper limit of normal value; AST /ALT higher than 2.5 times of upper limit of normal value；
• Routine Blood Test: WBC count <3.0×109/ L; PLT count <5×109/L ; or Hemoglobin <100g/L；
• Combined Pneumonia or other Severe systemic bacteria infection；
• Severe drug allergic history or anaphylaxis to 2 or more food or medicine；
• Other brain organic disease (eg. Brain cancer)；
• HIV+, Tumor Markers + ；
• Severe psychotic patients, cognitive dysfunction， or can not understand or sign the Consent Form；
• Other severe systemic or organic disease；
• Uncontrolled hypertension，blood pressure≥180mmHg/110 mmHg after treatment；
• Pregnancy；
• Enrollment in other trials in the last 3 months；
• Other criteria the investigator consider improper for inclusion.