Confirmation of RH (Radiation Hybrid) Map by Using Pulsed Field Gel Electrophoresis - PFGE - RH maps could be confirmed when, DNA from a cell line (e.g. CHG3 with chinese hamster nucleus plus human chromosome 21) was cleaved with rare cutter restriction enzymes like NotI, EagI, SalI, BssHI and MluI, which will produce large DNA fragments.
In each case, digested DNA was separated on agarose gel by the technique of pulsed field
gel electrophoresis (PFGE) and hybridized using Southern blot hybridization technique.

The markers close to each other on RH map, are expected to hybridize with same DNA fragment on the Southern blots.A comparison of RH map for human chromosome 21 with its PFGE map, demonstrated that the order of the markers and the distances between them are similar.