Regex Editor & Tester

This regex is intended to find Open Reading Frames (ORFs) in a DNA sequence, such as an Escherichia coli genome. It searches for sequences starting with the 'ATG' start codon, followed by at least 100 subsequent codons made of A, T, C, or G. While it attempts to end with a stop codon (TAG, TAA, or TGA), the use of square brackets creates a character class that matches any single character in the set `(`, `)`, `:`, `?`, `T`, `A`, `G` rather than a specific three-letter sequence. Using a non-capturing group with alternation like `(?:TAG|TAA|TGA)` would fix this.