ESR1 and obesity due to melanocortin 4 receptor deficiency: Our study identifies that dysregulation in genes like NOS3, TNF, BDNF, ESR1, ESR2, LMX1B, ATP1A2, OPRM1, NPY, THRB, NRXN3, SPARC, and MYT1l significantly impacts the interplay between obesity and chronic pain.