In this review, we conducted a comprehensive literature search using PubMed and Web of Science with the keywords “spinal muscular atrophy”, “biomarker” and advanced technologies such as “single-cell omics”, “nanopore and long-read sequencing” and “epigenetics” to identify and summarize current advances in SMA biomarker discovery and application. This evidence concerns the gene SMN1 and spinal muscular atrophy.