Let’s take, for example, the inbreeding coefficient F for population size N
Inbreeding reduces in proportion to N. Now, the deviation from hardy Weinberg equilibrium A, for alpha, is
A = 1/ 2n-1
Therefore as population increases A falls. In a 300 million population such as the US, A is about 1/(6x10e8). This means about 1 in 600m deleterious alleles exist per genome due to population limits, or in a 3 billion base pair typical human genome, about 5 alleles. For comparison,
From the 1000 Genomes Pilot data, we now see that an average individual typically carries ∼60 missense variants that severely damage protein structure and ∼100 loss-of-function variants.25
This means a doubling of population reduces the rate of deleterious mutations 2-4%.
Therefore although Population Control maybe justified for other reasons, it will increase the prevalence of genetic disorders by a measurable amount. These are very generous estimates because they ignore inbreeding which greatly lowers N.