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Chromosome 22 first human chromosome to be decoded

Chromosome 22

Chromosome 22 first human chromosome to be decoded

When the sequence of human Chromosome 22 was first reported in 1999, it was the longest, continuous stretch of DNA ever decoded and assembled. Chromosome 22 was chosen as the first of the 23 human chromosomes to decode because of its relatively small size and its association with several diseases. Seeing the organization of a human chromosome for the first time at the base-pair level paved the way for the rest of the Human Genome Project. Sequencing Chromosome 22 was an international collaboration between scientists in the U.S., England, Japan, France, Germany, and China.
1999