Ch 6 Pedigree Analysis Flashcards
pictorial representation of family history, outlining inheritance of one or more characteristics
pedigree
what are some pedigree characteristics of autosomal recessive traits?
- equal frequency between male and females
- tend to skip generations
- appears more frequently among consanguinity
what are some pedigree characteristics of autosomal dominant traits?
- equal frequency between male and females
- does not skip generations
- affected offspring has an affected parent
what are some pedigree characteristics of X-linked recessive traits?
- appear more frequently in males than females
- skips generations
- affected sons usually born to unaffected mothers
- never passed from father to son
what are some pedigree characteristics of X-linked dominant traits?
- appear more frequently in females than males
- does not skip generations
- affected fathers pass trait to all daughters; never to sons
what are some pedigree characteristics of Y-linked traits
- only males are affected
- passed from father to son
- does not skip generations
describe genetic mosaicism
different cells of the body have different genetic constitutions
what are monozygotic twins and how do they arise? how are they related genetically?
identical twins; genetically identical
arise when a single, fertilized egg splits early in development into two separate embryos
what are dizygotic twins and how do they arise? how are they related genetically?
nonidentical twins; only share 50% of genes
arise when two separate eggs are fertilized by different sperm, resulting in different zygotes
if a trait has higher concordance in monozygotic twins than dizygotic twins, what conclusions can one draw about the trait?
the trait is genetically influenced
if a trait is environmentally influenced, what conclusions can one d
