The C-value paradox states that the mass of DNA present in a nucleus does not always reflect the number of genes expressed by that organism. The c-value is an antiquated term used to describe the mass of DNA within a nucleus. This is paradoxical, as many complex organisms do not have the largest genomes. This is due to introns and other non-protein coding DNA, reducing the amount of DNA that is actually expressed.
The implications the c-value paradox has on genome size are that the size of an organism’s genome does not always reflect the number of genes or its relative complexity.