Animation on the D Loop

0:04 .mtDNA consists of two strands: a guanine  rich heavy strand, and a cytosine rich light  

0:10 strand. The heavy strand is the outer strand,  while the light strand is the inner strand.  

0:16 Because of their high variability in the human  population, these two non-coding regions,  

0:21 hypervariable region 1 and hypervariable region 2,  are the only regions which contain DNA information  

0:28 from mtDNA used in forensic testing.  Each hypervariable region contains  

0:34 only 350 of the 16569 nucleotides  present in an entire loop of mtDNA.