Similarities between a rice centromere and a human neocentromere. (a) Rice centromere 8 contains an approximately 750 kb CenH3-binding domain that is positioned off-center inside an approximately 1.2 Mb domain where H3 is dimethylated at the lysine that is residue 9 (dimethyl-K9 H3). Active genes are found in and around the CenH3-binding domain. Rice-specific centromeric repeats (CentO) are indicated. (b) Human neocentromere 10q25.3 contains an approximately 330 kb CenH3-binding domain contained in an approximately 700 kb region that can be precipitated with CREST#6 antibodies and is flanked by late-replicating regions. Shading is used to indicate potentially analogous regions, and the sizes shown are approximate.