miR-577 variants vary in 5′-end and male/female expression ratio.

Shown are all of the mir-577 variants expressed in human PFC at >100 counts per sample (Experiment 2). Variants that begin with GTA, i.e. that have an extra 5′-base compared to the canonical miRBase entry for mir-577, are indicated in bold. Although variants beginning with GTA and those beginning with TAG were expressed at roughly comparable levels, and had similar synaptic enrichment ratios, the GTA variants were expressed almost equally in males vs. females whereas the TAG variants were expressed predominantly in females. Synaptic enrichment ratio was calculated as the normalized synaptosome counts/mean counts in males.