Recording a Family Medical History or Pedigree

Abstract

A careful and detailed health history of the family is the basic prerequisite for any form of genetic counseling. It is essential to have detailed information about the proband’s relatives even when the proband himself is clearly suffering from a genetic defect of which the mode of inheritance has, ostensibly, been established. In genetics, there is always the possibility that a particular family will prove to be an exception. It happens, for instance, that a genetic defect, generally considered as autosomal-recessive, will be passed on as a dominant trait in some families. This, of course, also demonstrates that the same clinical disease has a separate genetic cause. A detailed pedigree gives us the necessary basic information for all further genetic considerations. It simplifies matters for oneself and the potentially required geneticist if the pedigree is drawn up with the symbols in common usage, such as those given in Figs. 2.1a, b.