Genomic blot is the type of Southern blot particularly used to analyze the mixture of DNA fragments derived from total genomic DNA. Because the genomic DNA is quite complicated, when it has been digested with the help of restriction enzymes, it produces a quite complex set of fragments ranging from tens of the bp to tens of the thousands of bp. Though, any specific gene will be reproducibly found on only one or a few particular fragments. A million identical cells will produce a million identical restriction fragments for any of the given gene, so probing a genomic Southern with a gene-specific probe will produce the pattern of perhaps one or of just a few bands.