Epigenetic regulation of gonadal and brain aromatase expression in a cichlid fish with environmental sex determination

We examined the methylation state of upstream intergenic regions associated with two aromatase genes (cyp19a1A and cyp19a1B) in P. pulcher, a cichlid fish with pH-based sex and male morph determination. Methylation levels in fry head and trunk and adult brain and gonad samples were assessed with a bisulfite amplicon sequencing assay and sequence data was processed through two pipelines to determine % methylation of individual CpG sites and abundance of specific patterns of methylated and unmethylated CpGs (i.e., epialleles). Overall design: Illumina-based bisulfite amplicon sequencing of four amplicons (two upstream of cyp19a1A and two upstream of cyp19a1B) to assess methylation state of CpGs in these regions