FIG. 1. (A) Schematic overview depicting a rapid and noninvasive method for extracting PCR-ready gDNA from adult zebrafish. Generated with BioRender. (B) Light microscopic images of cotton swabs before and after swabbing. Arrow indicates mucus on the wad. (C, D)mitopld was PCR amplified from gDNA extracted from clipped fin (C) or swabbed cotton wad (D), and 4 μL (C) and 8 μL (D) of PCRs were then analyzed using 4% agarose gel electrophoresis. (E, F) Electropherograms of PCR products in (C) and (D), respectively. +/+, WT mitopld; +/−, heterozygous mitopld mutant; −/−, homozygous mitopld mutant (8 bp deletion); bp, base pairs; buffer, DNA collection buffer; CW, cage water; DW, distilled water; E3, E3 embryo medium; gDNA, genomic DNA; L, DNA ladder; PCR, polymerase chain reaction; Q-tip, clean Q-tip; WT, wild-type.