Transcriptomics analyses also showed that control hMO-AO showed enrichment for “aged” human midbrain transcripts, and genes differentially expressed in LRRK2-G2019S hMO-AO were enriched for transcripts found in post-mortem PD midbrain tissue, thus supporting the relevance of their aging strategy. The gene discussed is LRRK2; the disease is Parkinson disease.