Dr Sladek's scientific contributions centre on establishing the role of gene transcription networks in complex traits. He identified key physiological roles for the orphan nuclear receptor ERRalpha in regulating the balance between lipolysis and lipogenesis and ERRbeta in regulating development of the chorion and trophoblast. He has developed methods to identify transcriptional networks de novo in panels of recombinant congenic mouse strains and to characterize transcriptional effects of cis-regulatory genetic variants that underlie complex genetic traits. Most recently, he collaborated with Drs Froguel, Polychronakos, Posner and Prentki to complete the first genome-wide association study (GWAS) to identify risk loci for type 2 diabetes.