In this single center study blood samples for biomarker analysis will be collected from patients with spinal muscular atrophy. Up to 21 mL blood will be drawn from eligible patients at a single visit.

Inclusion Criteria:

• Self-identified as 5q-autosomal recessive spinal muscular atrophy (SMA) type I, II or III as judged by their neurologist upon diagnosis
• Ability and willingness to provide blood samples
• Willingness (by the patient or patient's parents or legal guardian) to complete to their best ability a questionnaire which requests specific clinical and genetic information
• Able to participate and willing to give written informed consent or assent. Informed consent will be obtained from the patient, or the patient's parent or legal guardian.

Exclusion Criteria:

• Any known genetic condition other than spinal muscular atrophy, unless it is not interfering with the purpose of this study based on the Sponsor's judgment
• Participation in a clinical trial (except observational studies) within the previous 14 days
• Donation of blood or significant blood loss within three months prior to screening
• Concomitant disease or condition that could interfere with, or treatment of which might interfere with, the conduct of this study, or that would, in the opinion of the investigator, pose an unacceptable risk to the patient in this study

Patients with spinal muscular atrophy