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genome, genome version, assembly: These terms refer to a group of chromosome sequences refers to a group of chromosome sequences that you or another group assembled and made available. IGB designates these using the month and year they were published or made publicly available. For example, NCBI versions 35 and 36 of the human genome are considered to be two separate genome assemblies. Each one contains multiple chromosome sequences, including the expected chromosomes 1 to 22, X and Y. Other sequences, such as "chr22_random" are also considered distinct chromosomes for the purposes of display in IGB.
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