Quiz 2 MiniStudyguide Flashcards
Complementation
phenomenon in which the presence of two different mutant alleles in the same organism produces a wild-type phenotype.
Epistasis
inheritance pattern where one gene can mask the phenotypic effects of a different gene
Incomplete Dominance
Codominance
Both alleles are expressed
Sex Influenced inheritance example related to scur
what is heterozygote advantage and what are some possible mechanisms why it occurs?
universal blood donor
which one?
who can accept?
Universal blood recipient
Which one?
Who can they accept from?
in a cross for incomplete dominance, what is expected proportion of offspring with any
phenotype assuming large number of offspring
in incomplete penetrance what does percentage penetrance imply?
term for different extent of phenotypes seen in different individuals carrying the same trait or allele
given a pedigree representing an inheritance pattern, list various observations that are
know for that inheritance pattern
prion diseases
mechanisms of pathogenesis
genetic testing
individual test
genetic screening
population test
amniocentesis
take fetal cells from the amniotic fluid
chorionic villus sampling
take fetal cells from the fetal part of the placenta
sex-limited inheritance
locus heterogeneity
incomplete penetrance
haploinsufficiency
this mutation causes only 50% of the original protein to function
dominant negative mutation
acts antagonistically towards the wild type allele
variable expressivity
semilethal allele
lethal alleles that kill some individuals but not all
conditional lethal allele
allele that is lethal, but only under certain environmental conditions
temperature-sensitive lethal allele
allele that is lethal only in a certain environmental temperature range
manx cat related crosses
Manx cats are heterozygotes, the dominant homozygotes MM die in the embryonic phase, mm are not affected and are normal
levels of enzymes in three genotypes possible related to HexA gene which is associated
with autosomal recessive Tay-Sachs disease
given contribution from each additive allele, given baseline pheonotype with all
nonadditive alleles, determine the genotypes that show a particular phenotype
if you only classify gametes according to the number of additive alleles only, not the
actual genotype, then given a parental genotype, how many classes will you find?
examples of quantitative traits
given crosses with parental genotypes for quantitative traits, identify how many
offspring categories are possible
gene redundancy
phenomenon in which one gene compensates for the loss of function of another gene.
gene interaction
phenomenon in which two or more different traits genes influence the outcome of a single trait
gene interaction example
Corn kernels can have a purple color due to the dominant allele of one gene. When the alleles of a second gene are present in the homozygous recessive genotype, the kernel color is changed to red.
Suppose a genetic test shows that a woman has inherited the dominant BRCA1 allele that causes breast cancer. If she does not develop breast cancer in her lifetime, the phenomenon is called
incomplete penetrance
incomplete penetrance
pattern observed when a heterozygote does not show the trait associated with the dominant allele
lethal allele
allele that may cause death for an organism