Pedigree charts use shaded symbols to show organisms that have a particular trait, such as a defective gene, being traced in the chart. a breeder wants to make a pedigree chart of male horses to avoid breeding males that have a defective gene. what symbol would the horse breeder use to show a male who is affected by a defective gene?

 A male who is affected by a defective gene would have a symbol of shaded square that the horse breeder would use in the pedigree that is ■.

Pedigree can be described as a representation of a family and its lineage ( that is its ancestory and line of descent) in a form of flow chart ( using standard symbols), which depicts the pattern of inheritance of a particular disease.

For a male, a symbol of square is used and for a female, a symbol of square is used  ( that are shaded if the individuals are affected with a disease)