Genotyping of mtDNA in the isolated transmitochondrial cybrids.

<p>The ρ⁰ MDA-MB-231 cells have had their mtDNA removed and were used as mtDNA recipients and nuclear DNA donors; HeLamt231 and HeLamtFt correspond to mtDNA donors sharing the HeLa nuclear genome, but possessing mtDNA from the MDA-MB-231 cells and human fetal fibroblasts, respectively (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0023401#pone-0023401-t002" target="_blank">Table 2</a>). For identification of the C12084T mutation exclusively present in mtDNA of MDA-MB-231 cells (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0023401#pone-0023401-t001" target="_blank">Table 1</a>), the PCR products were digested with <i>Ear</i>I. Because of the gain of an <i>Ear</i>I site due to the C12084T mutation, 231mt231 cybrids carrying mtDNA from MDA-MB-231 cells produce 113- and 33-bp fragments, whereas 231mtFt cybrids carrying normal mtDNA without the mutation produce a 146-bp fragment.