Remaining novel menarche loci were found in or near to genes that are involved in a seemingly diverse range of biological functions (Supplementary Table 7). We used Ingenuity Pathway Analysis (IPA) to identify potential biological pathways common to these identified loci. Based on direct interactions only, we identified two significant functional networks containing 16 and 11 genes, respectively, of those genes nearest to the novel menarche loci (Supplementary Fig. 6). Network 1, related to “Gene Expression, Cellular Growth and Proliferation, Cellular Function and Maintenance”, covers a wide and non-specific range of biological pathways. Functions in Network 2 relate to “Lipid Metabolism, Small Molecule Biochemistry and Molecular Transport” (Supplementary Table 8). Central to Network 2 are RXRG and several genes involved in fatty acid biosynthesis, including several fatty acid binding proteins and ACSL1, which encodes a enzyme that converts free long-chain fatty acids into fatty acyl-CoA esters.
