Mutant Pigeon With Giant Legs

Markers are often located in non-coding areas of the DNA, where a specific base pattern repeats many times and these repeating segments are known and mapped. When a mutation occurs in a marker region, the mutation can be easily identified because the normal pattern of the repeating segment is known. Even if the marker region is located in non-coding DNA and the mutation has no visible effects, analyzing the marker region will allow scientists to see that a mutation has occurred.