The repeat units are also of various length, ranging from one to thousands of nucleotides. Generally known as variable number of tandem repeat (VNTR) loci (Nakamura et al., 1987), they are generally referred to as microsatellite loci when the repeat unit is short (two to six nucleotides in length) and as minisatellites when the repeat unit is eight base pairs or longer (Tautz, 1993).