Level 4 alignment. Thanks to Nanopore sequencing, I received the unique sequence of DNA. What is next to do with this sequence? How to determine the specific organism this DNA belongs to? The answer is to compare this sequence with the so-called reference sequence. It is the sequence which serves as a template. I can compare sequences by alignment. Sequence alignment is an arrangement of two or more sequences, highlighting their similarity. Comparing the sequences it could be that one of the sequences has a different nucleotide in one position. This is called a mismatch like the C to T in the red box. It could also happen that there is no nucleotide in the second sequence to the one in the first like the G in the blue box. This is called a gap, smetches in the alignment correspond to mutations, and gaps correspond to insertions or deletions. Alignment is an important instrument for finding a similarity between two or more sequences, due to its semi-conservative duplication mechanism, DNA transmits genetic information from generation to generation. Alignment sequences in the material are sometimes caused by errors or mutations in duplication, or by viruses and other mechanisms that move sequences between individuals and within chromosomes. Alignment between sequences indicates that both sequences originated from a common ancestor that contained the matching subsequences. In the case of genetic sequences, it implies that their carriers evolved from a common ancestor. Follow this link to play a fun game where you can learn more about alignment. Thank you for watching.