Top panel: observed Zn vs. Fe abundances for the stars in the Draco (red circles; Shetrone et al. 2001; Fulbright et al. 2004; Cohen & Huang 2009) and the Sextans (black circles; Shetrone et al. 2001; Honda et al. 2011) dSphs. For the Draco, the latest Subaru results are represented by small circles (T. Matsuno et al. 2018, in preparation). There is one Draco star showing a large enhancement of [Zn/H], deviating from those of the other stars. Such an anomalous Zn abundance can be attributed to the unique birth environment, in which interstellar matter is exclusively enriched by the ejecta of an SN Ia (see the text). Bottom panel: same as the top panel, but for Cr.