Existing Wording: A sequence of of base lengths and the associated operation, used to indicate which bases align (either a match/mismatch) with the reference, are deleted from the reference, and are insertions that are not in the reference. string of observed nucleotides. Observed nucleotides matching the reference are in capital letters. Observed nucleotides not matching the reference are in lower case letters. Use '-' a dash for deleted/missing nucleotides in the observed sequence. Allowable characters are A,T,C,G, a,t,c,g and -.

Proposed Wording: The CIGAR string of the sequence in extended CIGAR format relative to the reference sequence (Li H, Handsaker B, Wysoker A, et al. The sequence alignment/map format and SAMtools. Bioinformatics. 2009;25(16):2078.).

Comment:

The name "cigar" and the "base lengths" and "operation" suggest a CIGAR string of some type (whether CIGAR or extended CIGAR is not specified). However, "A, T, C, G, a, t, c, g, and -" suggests an alignment string instead of a CIGAR string. The specific intended format should be specified, please.