Similarity of the 2 involved alphoid subsets. Southern blot analysis of D1Z7 (pE25.a) and D7Z1 (D7Z1^6mer) alphoids in total human genome (A) digested with BamHI (b), EcoRI (e), and HindIII (h), as well as in DNAs from human monochromosomal mouse hybrid cells containing chromosome 1 (Neo1 and An4), 7 (Neo7 and NTI8), 2 (Neo2), 16 (Neo16), or 19 (Neo19) digested with EcoRI (B). Locations of dimmer (340 bp), tetramer (680 bp), and hexamer (1020 bp) are indicated to the left. D1Z7 and D7Z1 created a similar hybridization pattern with some cross hybridization with each other.