Essential Genetics 6th Edition by Daniel Hartl

تمرين 17

The accompanying diagram shows an electrophoresis gel in which DNA samples are placed ("loaded") in the depressions ("wells") at the top of the gel, and electrophoresis is carried out such that the DNA fragments move in the downward direction. The dashed lines on the right denote the positions to which DNA fragments of various sizes would migrate. The fragment sizes are given in kilobase (kb) pairs; 1 kb refers to a duplex DNA molecule 1000 base pairs in length. Also shown is the position of a DNA fragment corresponding to part of the coding region of a gene in DNA extracted from a homozygous wildtype (AA) organism. Assuming that a1 is a mutant allele that has a 2-kb insertion of DNA into the wildtype fragment, and that
is a mutant allele that has a 1-kb deletion within the wildtype fragment, show the positions at which DNA bands would be expected in each of the other genotypes shown.