example data:

Original pattern:
TMTMTMTMTETVTITITITX
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the X is removed earlier in the program as it never occurs in the larger sequence therefore when i search the pattern is never found.

modified pattern:TMTMTMTMTETVTITITIT
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However... the character which X represents (which is any alphabetical character) must be found from the larger pattern.hence the a-z then i search through the larger string untill the pattern is found

target pattern:
TMTMTMTMTETVTITITIT[M]or[Q] etc
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and ideally remove the completed pattern which matched the regex so $var4 would equal TMTMTMTMTETVTITITITM or TMTMTMTMTETVTITITITQ apologies for being verbose.