Mendelian Inheritance

  1. monohybrid cross
    • Crossed two variants differing in only one trait
    • Helps show law of segregation
  2. Dominance
    the trait that appears in the F1 generation
  3. Law of segregation
    • alleles of a locus are placed into separate gametes during meiosis
    • Each gamete receives only one or the other allele of a locus
    • Each gamete has one allele of every locus
  4. Test cross
    • - cross to test whether phenotype corresponds to homozygous dominant genotype or heterozygous genotype
    • Always will cross of dominant(homo- or hetero-) vs recessive
    • TTxtt
    • Ttxtt
  5. Law of independent assortment
    Either allele of one locus can go together in a gamete with either allele of a 2nd unlinked locus

    dihybrid cross
  6. Recessive Null
    • no functional protein is producedgenetic null
    • – gene is lostfunctional null
    • – no protein function
  7. loss-of-function alleles (LOF)
    • a protein that doesn’t function as much as or in the same way as the wildtype protein
    • Wildtype alleles are dominant to recessive alleles
  8. Dominant
    Gain-of-function (GOF)
    • protein functions is a new way
    • more protein is made than in wildtype
    • protein can not be regulated as in wildtype
  9. Dominant-negative (DN)
    • a mutated protein disrupts the function of wildtype proteins
    • dominant alleles are dominant to wildtype
  10. Incomplete dominance
    Heterozygosity makes 3rd phenotype intermediate to the homozygous phenotypes

    Blue, light blue, no color
  11. Co-dominance
    heterozygosity produces a single unique phenotype different from either homozygous condition
  12. Overdominance
    heterozygosity creates a phenotype better or worse than homozygosity of either locus
  13. Lethality
    homozygosity of an allele kills the cell or organism
  14. Penetrance
    • measures of variation in expression of a given allele occurs
    • incomplete penetrance- lack of effect a deleterious allele has in an individual
  15. Supressor
    • -mutation A and mutation B. B blocks A
    • Enhancer-more robust expression
  16. wild-type alleles
    • prevalent alleles in a population
    • encoded proteins are considered
    • -normal function
    • -normal expression level
  17. mutant alleles
    • less common in natural pop, but >1%
    • alters expression level or functionality of protein
  18. Barr body
    inactive X chromosome
  19. sex linkage
    • If sons of affected mothers then sex llinked dom/rec
    • If daughters of affected fathers then sex linked dom/rec
Card Set
Mendelian Inheritance