Question

in the sanger (dideoxy) method for dna sequencing, researchers add a small amount of a dideoxynucleoside triphosphate, such as ddctp, to the sequencing reaction along with a larger amount of the corresponding deoxynucleoside, such as dctp. what result would researchers observe if they omitted dctp from the sequencing reaction?

Answer 1

Only a single band would be observed in the lane representing C.

Step-by-step explanation:

Chain elongation would terminate at the very first incorporation of C so the seqencing would only go to the first C base.

As you can see in the picture attached ddCTP lacks the 3' -OH group that is required to continue elongation so whenever a ddNTP is added elongation is temrinated.