Adverse Occurrence type:
Alerting signals, symptoms, evidence of occurrence:
At 10 months of age, the child developed muscle weakness and was unable to sit, stand, or crawl. A clinical diagnosis of SMA was made at 1 year of age. Molecular genetic investigations revealed homozygosity for the common deletion mutation at SMN1, which confirmed the diagnosis of SMA. .
Demonstration of imputability or root cause:
Carrier screening for SMA was performed on both gamete donors after this report. Both individuals were confirmed to carry one copy of the SMN1 deletion mutation. There are reported births of other offspring from each of these donors, but none of the other children have been reported to have any symptoms or diagnoses of SMA.