ALPHA-SATELLITE DNA IN NEOTROPICAL PRIMATES (PLATYRRHINI)

The alpha satellite DNA of Old World (catarrhine) primates usually con sists of similar, but not identical, ca. 170 bp sequences repeated tan demly hundreds to thousands of times. The 170 bp monomeric repeats are components of higher-order repeats, many of which are chromosome spec ific. Alpha satellites are found exclusively in centromeric regions wh ere they appear to play a role in centromere function. We have found t hat alpha satellite DNA in neotropical (New World; platyrrhine) primat es is very similar to its Old World counterpart: it consists of diverg ent ca. 170 bp subsequences that are arranged in tandem arrays with a ca. 340 bp periodicity. New and Old World alpha satellites share about 64% sequence identity overall, and contain several short sequence mot ifs that appear to be highly conserved. One exception to the tandemly arrayed 340 bp motif has been found: the major alpha satellite array i n Chiropotes satanas (black bearded saki) has a 539 bp repeat unit tha t consists of a 338 bp dimer together with a duplication of 33 bp of t he first monomeric unit and 168 bp of the second monomeric unit.