Question

If the random sequences were prepared in a way that maintained the local base composition by producing them from overlapping fragments of sequence, the distribution of scores has a _______ standard deviation that is closer to the distribution of the natural sequences.

(a) lowest

(b) higher

(c) lower

(d) moderate

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This key question is from Assessing the Significance of Sequence Alignments topic in division Sequence Alignment of Bioinformatics

Answer 1

Right option is (c) lower

Explanation: The conclusion from the above is that the presence of conserved local patterns can influence the score in statistical tests such that an alignment can appear to be more significant than it actually is. Although this study was done using the Smith-Waterman algorithm with nucleic acids, the same cautionary note applies for other types of alignments.