Fine mapping of SRT1. Fine mapping of SRT1. To fine map the SRT1 locus, we compared the sequencing data and developed a set of InDel markers in the 5 Mb region of chromosome 4 identified by BSA-seq. Linkage analysis using these molecular markers first placed SRT1 on a short genomic region between ST_8 and ST_23. Further linkage analysis using markers developed in this region delimited SRT1 within a region of ∼231 kb between ST_18 and STSNP_3, with tight linkage to ST_5. Genetic distances in cM between two neighboring markers are indicated on left side of chromosome. Fredrick Mwamburi Mjomba et al. G3 2016;6:2013-2021 ©2016 by Genetics Society of America