Taguchi K, Chen L, Usawachintachit M, et al. - Since there is a lack of knowledge regarding the mechanism whereby obesity is associated with kidney stone formation, researchers applied a transcriptomics approach to determine the missing link between these two epidemic diseases. Using two RNA-sequencing approaches, they explored gene expression profiling of patients with nephrolithiasis: a contrast between renal papilla tissue with and without the presence of calcified Randall’s plaques (RP), and contrast between the papilla, medulla, and cortex regions from within a single recurrent stone forming kidney. Impairment of lipid metabolism in renal papilla tissue comprising RP connected to downregulation of fatty acid binding protein (FABP) 4 was shown by the overlay of these two RNA-sequencing datasets. A link between FABP4 downregulation and renal stone formation was confirmed on immunohistochemistry of human kidney specimens and in a microarray study of renal tissue from a nephrolithiasis mouse model. Overall, a crucial role of FABP4 in kidney stone formation which was previously unrecognized was revealed in this study, affording a feasible mechanism to describe the connection between nephrolithiasis and metabolic syndrome.