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Scientific evidences have revealed the important role of alpha satellite, also known as alphoid DNA, in centromere function. This is the only known DNA localized in the centromeric regions of all normal human chromosomes. Moreover, natural and artificial chromosome rearrangements have been used to localize human X and Y centromeres. However, these evidences failed to consider the role of nonalphoid DNAs.

A study localizes the centromere function in a Drosophila minichromosome Dp1187. The analyses of the transmission behavior of Dp117 identified sequences necessary for chromosome inheritance within the centric heterochromatin. The vital sector of the centromere is incorporated within a 220kb region which also includes significant amounts of complex DNA. Completely normal inheritance also needs an equivalent of 200kb on either side of the essential core. This flanking DNA contains highly repeated sequences.

The nod+, a kinesin-like gene needed for the meiotic transmission of achiasmate chromosome, helps in the transmission of the Drosophila minichromosome Dp1187. The chromosome transmission develops forces outside the kinetochore for the attachment of achiasmate chromosome to the metaphase spindle. The nod interactions are seen at a region which is not required for centromere function.