We applied force curve mapping to chromosomes. Two types of artifacts were observed in the adhesion force images thus obtained. Location shifting between the adhesion and topographic images and deformation of the measured adhesive structure were seen. These artifacts are explained by theoretical analysis to be the result of cantilever tip sliding due to cantilever deflection during the adhesion force measurements. Analysis also showed that this tip sliding caused a small, highly adhesive region to escape measurement. The artifacts observed are not small enough to be negligible for molecular-size applications, and therefore, possible solutions to eliminate them are discussed.