A genomic region containing RNF212 is associated with sexually-dimorphic recombination rate variation in wild Soay sheep (Ovis aries). Susan E. Johnston1, Jon Slate2, Josephine M. Pemberton1 S3 Appendix - Predicted location of RNF212 on the Sheep genome Oar_v3.1 The locus RNF212 has not been annotated on the domestic sheep genome (Oar_v3.1). Here, we present evidence that RNF212 occurs within the region most highly associated with autosomal crossover count (ACC). Sheep sequences for RNF212 were obtained from Genbank (Accession Numbers provided in Figure S6 and aligned against the Oar_v3.1 genome sequence using BLAST v2.2.27+ using the default parameters and a word size of 15 to determine if the locus was likely to be present within this region. Matches of length < 50 bp and matching bases of < 95% were discarded .The strongest associations on the assembled genome sequence were at the sub-telomeric region of chromosome 6 identified in the main results, falling between positions 116,427,802 and 116,446,904 (Figure S6). This positioned RNF212 between an uncharacterised protein (orthologous to Tmed11) and FGFRL1, and suggested that its lack of annotation on the domestic sheep genome is due to its occurrence across a gap in contiguous sequences (Figure S7). Gene order in this region showed high similarity to gene orders obtained for homologous genome regions in cow (UMD3.1), dog (CanFam3.1), human (GRCh38) and mouse (GRCm38); all annotations were obtained from Ensembl build v1.79 [1]. The alignment of RNF212 shown in Figures 5 and S7 is to sequence XM_012167676.1. 1. Cunningham F, Amode MR, Barrell D, Beal K, Billis K, Brent S, et al. Ensembl 2015. Nucleic Acids Res. 2014;43: D662–D669. doi:10.1093/nar/gku1010