Figure 3

PCR amplification of genomic DNA yields a 1,003-bp amplicon containing the 633-bp region (sequence change 2 in Figure2A) in Mexican (RC) surface fish (SF) and Pachón (Pa), Los Sabinos (LS), Tinaja (Ti), Jineo (Ji), Chica (Ch), and Molino (Mo) cavefish populations and a 370-bp amplicon lacking the 633-bp region in the Texas (Tx) surface fish population. PCR amplification was carried out using primers flanking the 633-bp region in Pachón cavefish (see Methods).