09-27 smc

Distribution of repetitive DNA elements within Exon / Intron structures

    The 14  exons [numbered dark-green units] for a single gene constitute a very small portion of the total 50 Kbp region. The introns  [light-green areas] include a number of families of repetitive DNA sequences, shown in the exploded view below. These include short interspersed repeats (SINES, including Alu family sequences), long interspersed repeats (LINEs, including the L1 family), long tandem repeats (LTRs), and simple sequence repeats (SSRs), also known as VNTRs or  micro- or minisatellites. Note that the SSRs are described as two- or four-base motifs that are repeated n times each.

Figure modified from 2002 by Griffiths et al.; all text material 2013 by Steven M. Carr