Those regions are thought to contain few genes, if any.
At the other end of the scale are viruses which contain more than 200 genes.
Most chromosomes probably contain more than 2,000 individual genes each.
Chromosome 8 is likely to contain between 700 and 1,000 genes.
Chromosome 7 is likely to contain between 1,000 and 1,400 genes.
For one thing, all of these genomes have turned out to contain far more novel genes than had been expected.
The genome contains 513 genes, 465 of which code for protein.
Its total genome is 1.5 Mb long and contains 1512 genes.
Its length is 15,179 nucleotides and it contains 13 genes.
It is estimated that chromosome 21 contains 200 to 250 genes.
