I am new to processing protein protein interaction data. I downloaded BIOGRID interaction data for S.cerevisiae from SGD http://www.yeastgenome.org/download-data/curation and started analysing them.
I observed that some genetic interactions have the attribute 'phenotype' as inviable/vegetative growth:decreased/ vegetative, whereas all physical interactions don't have any associated phenotype.
Since I'm not from a Biology background, I would like to know what these phenotypes really mean and why do they only appear under genetic interactions.
In cell biology, phenotype usually refers to characteristics observed after loss of function of a gene. The phenotype of a genetic interaction is thus the phenotype observed when the two genes have been inactivated. However, genetic interaction usually means that the phenotype of the inactivation of the two genes is somehow different of the phenotype of the inactivation of each gene separately. There's no phenotype associate with physical interactions because nobody (as far as I know) systematically records what happens when a physical interaction is disrupted.
If you're going to work with biological data, I suggest you read a biology textbook relevant to the area of biology you're dealing with.
Thank you very much for the explanation! Can you please recommend a good text book to be referred when working with functional genomics data?