It is far more common to find human genetic disease caused by alleles than by alleles because?

Answer 1

You are repeating yourself.

If a dominant gene inhibits reproduction, it will eventually work itself out of the population.

Whereas a recessive gene can sporadically pop up.

However, a gene such as a "cancer gene" might not inhibit reproduction, and thus could perpetuate at a higher rate in either a dominant or recessive form.

There is a theory called "Heterozygote Advantage" that certain genetic disorders such as Cystic Fibrosis or Sickle Cell Anemia may actually provide a protective advantage when found as a heterozygote recessive, but is deadly when the person inherits both genes.

Answer 2

It is far more common to find human genetic disease caused by alleles than by alleles because individuals inherit two alleles for each gene (one from each parent), increasing the chances of inheriting at least one disease-causing allele. Alleles can be recessive or dominant, requiring different inheritance patterns to cause disease.