Sort of. Current DNA sequencing technology breaks the DNA up into short pieces, sequences the pieces, and then uses software to reassemble them by looking for places where the fragmentary sequences overlap. It's basically the mother of all DIFFs. Telomeric DNA (the DNA at the ends of chromosomes) consists of many repetitions of the same short (<10) sequence of base pairs, so there is no pattern for the reassembly process to latch on to. So it's not the ends per se that are problematic, it's any long sequence that is devoid of structure. Chimps, for example, have telomeric DNA in the middle of one of their chromosomes. This is an example of "smoking gun" evidence for macroevolution. See http://www.gate.net/~rwms/hum_ape_chrom.html