A zoo blot or garden blot is a type of Southern blot that demonstrates the similarity between specific, usually protein-coding, DNA sequences of different species. A zoo blot compares animal species while a garden blot compares plant species.
In order to understand the degree to which a particular gene is similar from species to species, DNA preparations from a set of species is isolated and spread over a surface. The sequence of interest is labeled and allowed to hybridize to the prepared DNA. Usually, the labeled DNA is marked with a radioactive isotope of phosphorus. The hybridization is a process that happens spontaneously: DNA pairs with complementary strands. The hybridization, however, is not perfect.
The hybridization of two strands will happen even when the strands are similar but not identical. This procedure is used to detect similar or exact relationships between the DNA in question and other organisms, so the technique takes advantage of non-exact hybridization. It also allows you judge the locations of introns and exons as the latter will be far more conserved than the former.
Famous quotes containing the words zoo and/or blot:
“The zoo cannot but disappoint. The public purpose of zoos is to offer visitors the opportunity of looking at animals. Yet nowhere in a zoo can a stranger encounter the look of an animal. At the most, the animal’s gaze flickers and passes on. They look sideways. They look blindly beyond.”
—John Berger (b. 1926)
“Either disperse these mists, which blot and fill
My perspective, still, as they pass:
Or else remove me hence unto that hill
Where I shall need no glass.”
—Henry Vaughan (1622–1695)