The mammalian cell line CHO-K1 has 24,383 genes. After 70 doublings (from a starting number of cells, 1) a total of ~4,000 mutations have occurred in the overall population of cells (i.e. not all in one cell), due to incorrect DNA breakage repairs (non-homologous end joining), with the mutations randomly distributed throughout the genome. Assuming that 2% of CHO genome consists of crucial genetic information (1.5% coding and 0.5% regulatory). What number of genes will be affected by these mutations?
I was thinking that the mutations should be spread randomly and so 24383*70/4000 genes may be affected but doesn't that assume the mutations are one per gene and the affected areas are actually important to protein expression?