BSN and obesity due to melanocortin 4 receptor deficiency: However, our analyses also highlighted two new genes: BSN, encoding a presynaptic protein with a role in exocytosis-mediated neurotransmitter release38, which we have shown recently is associated with increased risk of severe obesity, metabolic dysfunction-associated steatotic liver disease and type 2 diabetes39; and CORO1A (n = 415 carriers, β = 0.98 ± 0.215; P = 5.6 × 10−6), which encodes a WD repeat protein involved in cell cycle progression, signal transduction, apoptosis and gene regulation40—a gene previously unlinked with obesity.