Common recessive genes

Worldwide, the haemoglobinopathies are the most common
autosomal recessive disorders. In certain populations, 1 in
6 people are carriers. In white populations 1 in 10 people carry
the C282Y haemochromatosis mutation. One in 400 people are
therefore homozygous for this mutation, although only one
third to one half have clinical signs owing to iron overload.
In northern Europeans the commonest autosomal recessive
disorder of childhood is cystic fibrosis. Approximately 1 in
25 of the population are carriers. In one couple out of every
625, both partners will be carriers, resulting in an incidence of
about 1 in 2500 for cystic fibrosis.