Freshly resected fat from the neck was placed immediately into RNAlater (Qiagen). We extracted total cellular RNA from tissue using an RNeasy minikit (Qiagen) according to instructions. Quantity and purity were assessed by ultraviolet absorbance at 260 and 280 nm. cDNA was prepared from 6 ng/μL of RNA using the High Capacity cDNA Reverse Transcription kit (Applied Biosystems) according to the manufacturer’s instructions. 6 μL (36 ng) of cDNA was used in a 20 μL PCR using TaqMan® Gene Expression Assays with a FAM dye label for the following genes (Supplementary Tables 3 and 5): uncoupling protein 1 (UCP1), type 2 deiodinase (DIO2), β3-adrenergic receptor (ADRB3), peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PPARGC1A, also known as PGC1α), cell death-inducing DNA fragmentation factor alpha-like effector A (CIDEA), PRD1-BF1-RIZ1 homologous domain containing 16 (PRDM16), receptor-interacting protein 140 (NRIP1, also known as RIP140); fibrillin 1 (FBN1); engrailed 1 (EN1); homeobox A5 (HOXA5); homeobox C9 (HOXC9); and leptin (LEP). Quantitative RT-PCR assays were run in duplicates and quantitated in the ABI Prism 7900 sequence detection system. The values were normalized to the expression of TATA-binding protein (TBP) in each sample, and results were expressed as ratios in arbitrary units.