Chromosome 22
Chromosome 22 is one of the 23 pairs of chromosomes in human cells. Humans normally have two copies of chromosome 22 in each cell. Chromosome 22 is the second smallest human chromosome, spanning about 51 million DNA base pairs and representing between 1.5 and 2% of the total DNA in cells.
| Chromosome 22 | |
|---|---|
Human chromosome 22 pair after G-banding. One is from mother, one is from father. | |
Chromosome 22 pair in human male karyogram. | |
| Features | |
| Length (bp) | 51,324,926 bp (CHM13) |
| No. of genes | 417 (CCDS) |
| Type | Autosome |
| Centromere position | Acrocentric (15.0 Mbp) |
| Complete gene lists | |
| CCDS | Gene list |
| HGNC | Gene list |
| UniProt | Gene list |
| NCBI | Gene list |
| External map viewers | |
| Ensembl | Chromosome 22 |
| Entrez | Chromosome 22 |
| NCBI | Chromosome 22 |
| UCSC | Chromosome 22 |
| Full DNA sequences | |
| RefSeq | NC_000022 (FASTA) |
| GenBank | CM000684 (FASTA) |
In 1999, researchers working on the Human Genome Project announced they had determined the sequence of base pairs that make up this chromosome. Chromosome 22 was the first human chromosome to be fully sequenced.
Human chromosomes are numbered by their apparent size in the karyotype, with chromosome 1 being the largest and chromosome 22 having originally been identified as the smallest. However, genome sequencing has revealed that chromosome 21 is actually smaller than chromosome 22.