The incidence of genetic disease and the impact on man of an altered mutation rate.

In order to adequately assess the genetic risks to man of an altered mutation rate, it is necessary to know the naturally occurring frequency of mutation-maintained genetic ill-health and the burden that such defects impose. The relevant data that are available are largely inadequate to determine the incidence of genetic disease that is maintained by mutation, and measures of various aspects of the social and personal burdens due to hereditary ill-health are almost wholly lacking. It is suggested that the creation of individual and family histories, using large scale automatic record linkage and existing files of vital and ill-health records, may be a useful approach to these kinds of problems. Using such linked individual health histories, new data are presented that relate to measures of the burden due to childhood dominant and recessive diseases and congenital malformations.