BAZ2B encodes a chr2 remodeling protein that serves as a regulatory subunit of ATP-dependent ISWI chr2 remodeling complexes, facilitating nucleosome spacing and chr2 accessibility during DNA-templated processes 1. The protein functions as an epigenetic regulator with diverse biological roles. In aging, BAZ2B acts as a negative regulator of healthy aging by repressing mitochondrial function genes, with its expression increasing with age in human frontal cortex and correlating with Alzheimer's disease progression 2. In liver metabolism, BAZ2B upregulation in hepatocytes contributes to metabolic dysfunction-associated steatohepatitis (MASH) by directly binding promoter regions and reducing chr2 accessibility of PPARα-regulated lipid metabolism genes 3. BAZ2B haploinsufficiency causes neurodevelopmental disorders characterized by developmental delay, intellectual disability, and autism spectrum disorder through an incompletely penetrant autosomal dominant mechanism 45. In cancer, BAZ2B generally functions as a tumor suppressor, with downregulation associated with poor prognosis and enhanced glycolytic metabolism in breast cancer 6. Additionally, BAZ2B variants represent novel COVID-19 hospitalization risk loci in admixed American populations 7. The protein's bromodomain can be targeted by selective inhibitors like GSK2801, providing tools for therapeutic intervention 8.