21. CENP-A associates with the centromere and is necessary for assembly of the kinetochore. 22. Instead, they remain tightly associated with the centromeres of non-disjoined sister chromatids. 23. Anti-centromere and anti-p62 antibodies are also found in ( PBC ). 24. The inner centromere proteins ( INCENPs ), 25. Yeast, " Drosophila " and mammals all have heterochromatin flanking their centromeres . 26. Finally, an interesting recent discovery is having double-stranded RNA specify centromere location. 27. This allows the detection of antibodies to mitosis-specific antigens, such as centromere antibodies. 28. Thus, a positive anti-centromere antibody finding is strongly suggestive of limited systemic scleroderma. 29. Overexpression of CENPA and CENPH ( centromere protein H ) is also associated with colorectal cancer. 30. The homologous nature of the two viral centromeres would incite the grouping of both sets into tetrads.