generations
A pedigree is a chart which shows the inheritance of a trait over several generations. A pedigree is commonly created for families, as it can be used to outlines the inheritance patterns of familial traits or genetic disorders. It can be used to demonstrate autosomal dominant or recessive inheritance, or sex-linked inheritance. Figure below shows a pedigree depicting recessive inheritance of a disorder through three generations. The trait is thought to be recessive as for the two individuals with the trait, neither has a parent who also has the trait. Geneticists may also be able to determine whether individuals with the trait in question are heterozygous or homozygous for the allele associated with the trait. When alleles are added to the pedigree shown A or a , recessive inheritance in conformed.