SPOT SMA is a prospective NIH-supported clinical study targeting pre-symptomatic or recently diagnosed infants and children with Spinal Muscular Atrophy (SMA) types 1, 2, or 3 and their healthy control siblings less than 36 months of age at the time of study enrollment. The main objective of the study is to prospectively collect longitudinal clinical outcomes and provide counseling and education to parents of newly diagnosed children. The study will assess the impact of current standard of care management paradigms and interventions on health outcomes in newly diagnosed SMA infants and children with type 1, 2 or 3 and age appropriate controls. There is no investigational drug and no specific intervention in this study. Rather, the investigators will document outcomes related to current therapies provided to participating subjects, and will educate participants about possible clinical trial opportunities.

Overview of data to be collected from enrolled infants followed longitudinally and entered into the NBSTRN Longitudinal Pediatric Data Resource

1. Past medical history relevant to pregnancy, delivery, complications in the immediate neonatal period, birth parameters, family history and any medical problems other than SMA (ie prematurity, etc)

2. Ongoing medical history indicating problems related to the following areas:

   feeding, growth, respiratory status including use of cough assist and bilevel respiratory support, gastrointestinal issues, cardiac symptoms, neurologic symptoms or signs including muscle weakness, hospitalizations, ER visits, other adverse events

3. Assessment of dietary intake and use of nutritional supplements

4. Surgical history and ongoing documentation of assessments and need for g-tube, Nissen, tympanostomy, adenoidectomy/tonsillectomy or other airway surgeries, and orthopedic procedures

5. Caregiver obtained developmental history and documentation of newly acquired and/or loss of previously acquired gross motor skills at the time of each visit

6. Documentation of caregiver reported outcomes

7. Documentation of anthropometric measures, vital signs, general physical examination parameters

8. Neurological examination using standardized tools

9. Time to death, permanent invasive ventilation and/or need for > 16 hours/day of bilevel respiratory support

10. Specific assessment of motor function as measured using age appropriate motor outcome measures such as: the Children's Hospital of Philadelphia Infant Tests of Neuromuscular Disorders (CHOP-INTEND), Test of Infant Motor Performance Screening Inventory, WHO motor milestones or others, and Hammersmith Functional Motor Scale for SMA Expanded for children 18 months and older

11. Electrophysiologic studies such as maximum ulnar compound muscle action potential (CMAP) amplitude and area

12. Documentation of range of motion, development of limb contractures and/or presence of scoliosis, lordosis, hip dysplasia or other orthopedic outcomes

13. Additional optional exploratory biomarker assessments

14. DEXA measurements to assess body composition and bone density

15. The option to enroll in an autopsy study at the time of death to contribute samples to a research biorepository

Normal control subjects such as unaffected siblings will undergo these same measurements, as applicable. Unaffected parents' participation will be limited to collection and banking of blood and cell lines.

Inclusion Criteria:

• For affected subjects: genetic diagnosis of SMA
• For unaffected family members: parent or sibling of any age (without genetic diagnosis of SMA) of affected subject enrolled in study

Exclusion Criteria:

• None

Pre-symptomatic or newly diagnosed infants and children with Spinal Muscular Atrophy (SMA) types 1, 2, or 3; OR unaffected parents and siblings of enrolled infants and children with SMA; OR control subjects: infants and children who are not affected with SMA

The National Institute of Child Health and Human Development has a contract with the American College of Medical Genomics and the Newborn Screening Translational Research Network (NBSTRN) in collaboration with the bioinformatics group at the Cincinnati Children's Hospital to develop a national database for data capture and management for all the follow-up data to be collected for those who agree to participate in the research study. The investigators will share deidentified data with the NBSTRN database.

The investigators will also submit relevant associated data (e.g., phenotype data) to an NIH-designated data repository in a timely manner, as indicated by the NIH Genomic Data Sharing policy.

Aggregate Data will be available for submission/general research use.