Genotypic variation within an individual

[dscuffell]

I've been working with some SNP data. Basic biology helps me understand that any SNP will have a frequency of variation with a population, and that by sampling that population we can understand the frequency of variation for that SNP. However as an individual's genome is made up of all the DNA from a poplulation of cells, surely there will also be SNP variation with the individual ? Is this the case, and if so how would this variation within the individual be quantified? 

Edited April 14, 2020 by dscuffell
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