The requirement of DNA polymerases to have a primer causes a problem at the ends of linear templates. The leading strand synthesis can proceed to the end of its template strand, but lagging strand syn...The requirement of DNA polymerases to have a primer causes a problem at the ends of linear templates. The leading strand synthesis can proceed to the end of its template strand, but lagging strand synthesis cannot. A 3’ overhang is left after the replication fork has finished, and part of the chromosome is not copied into new DNA. If nothing else were done, the chromosome would become progressively shorter after each round of replication.
