In: Biology
how to find genotype from an electro gram with base pairs
Electropherogram is the result of electrophoresis where in agarose or polyacrylamide gel, the DNA fragments are separated on the basis of their sizes. Depending upon the size difference in different alleles we can determine the genotype of a organism.
Let us take an example. One trait is controlled by two alleles A and a. A allele has a restriction site which have been mutated in allele 'a'. Suppose allele A and 'a' are 300 bp long and the restriction enzyme digestion of allele A produce 200 and 100bp band as 300bp has been cleaved by RE for only allele A. This RE site have been mutated in allele 'a' and thus allele 'a' produce only 300bpband after RE digestion.
Now in case of Genotype AA - two bands will appear after RE digestion . One set of bands will be 200bp long and another set will be 100bp long.
In case genotype aa, only one type of bands will appear and that will be 300b long.
In case of genotype Aa, three sets of bands will appear, 200 bp, 100bp (both from allele A) and 300bp (from alllele a).
In this way we can differentiate different genotypes.
The electropherogram is shown below: