Fig. 3

Main approaches used for whole-genome amplification of single cells. a Degenerate Oligonucleotide-primed polymerase chain reaction (DOP-PCR) uses primers with common sequences at the 5′- and 3′-ends, but six random nucleotides near the 3′-end to allow hybridization at many sites throughout the genome; b multiple displacement amplification (MDA) uses φ29 DNA polymerase and random primers in a non-PCR based amplification reaction in which newly-synthesized strands are displaced from the original DNA molecule and serve as templates for additional DNA synthesis, resulting in a hyper-branched network; c multiple annealing and looping based amplification cycles (MALBAC) uses random primers with a common sequence at the 5′-end to amplify only the original template DNA and semi-amplicons. Full amplicons have complementary ends that allow the formation of closed-loop structures that prevent further amplification [15]