Molecular Biology/random hexamers
genejockey wrote at 2010-03-02 21:56:36
Random primers will favor 5' ends in cDNA synthesis. Priming will be random, extention will not, it will always progress 5->3.
Rafa wrote at 2015-11-15 20:58:37
Dear First answer,
I think that you did not take time to read the question of Thomas. We know that random hexamers will bind all along the RNA molecule, but as retrotranscription takes place from 5´ to 3´. We can imagine one mRNA that have 50 random hexamers "randomly distributed along the sequence", so after elongating them efficienlty only half of the hexamers will contain the 5´ of the mRNA, but there will be 25 primers that will not contain the 3´ half of the mRNA. If there is no bias, mean that at the end there is no difference between 5´ to 3´. Look for the 5´- to 3´ exonuclease activity of the Reverse transcriptase.