Question

Which of the given statements is incorrect about All-against-all Self-comparison?

(a) A comparison of each protein in the proteome with all other proteins distinguishes unique proteins from proteins that have arisen from gene duplication, and also reveals the number of protein families but the domain content of these proteins cannot be known

(b) In all-against-all proteome comparison, each protein is used as a query in a similarity search against the remaining proteome

(c) In all-against-all proteome comparison, the similar sequences are ranked by the quality and length of the alignments found

(d) In all-against-all proteome comparison, The search is conducted with each alignment score receiving a statistical evaluation (P or E value)

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This is a very interesting question from Comparative Genomics topic in section Collecting & Storing Sequences in Laboratory of Bioinformatics

Answer 1

The correct answer is (a) A comparison of each protein in the proteome with all other proteins distinguishes unique proteins from proteins that have arisen from gene duplication, and also reveals the number of protein families but the domain content of these proteins cannot be known

For explanation I would say: The domain content of these proteins may also be analyzed. in all-against-all proteome comparison, a match between a query sequence and another proteome sequence with the same domain structure will produce a high-scoring, highly significant alignment. These proteins are designated paralogs because they have almost certainly originated from a gene duplication event.