intragenic
mutations within the same gene
extragenic
between different genes
null allele
non functional and likely recessive to all other alleles
incomplete dominance
appearance of a third phenotype that “blends” two parental ones
codominace
heterozygote displays both parental phenotypes
is incomplete dominance and codominace an example of mendelian relationships
no
variable penetrance
they all have the genotype, but only a few of them show it (all or nothing)
someone having low penetrance means what
that even though the dominant allele was there, it didn’t show through to cause a phenotype
variable expressivity
the dominant allele will always sow up but it shows up as multiple different phenotypes
do dominant lethal alleles skew mendelian ratios
yes (often 2:1 as one type dies)
genes that affect more than a single phenotype are called
pleiotropic
signature of dominant lethal alleles
2 dominant : 1 recessive
polygenic inheritance
many genes affecting the same phenotype
examples of qualitative traits
height, skin, skin color
difference between pleiotropy and polygenic
pleiotropy refers to one gene influencing multiple traits
Polygenic refers to multiple genes influencing one trait
complementing mutation is what
2 genes involved (non-allelic)
non complementing mutation is what
single gene involved (allelic)
supressor mutations lead to what
wild type phenotype
complementation group tests look for what
are these mutations in the same or different genes
if the diploid grows without arginine, then the mutant is on the same gene or different genes
different genes
auxotroph
does not grow in MM
supplementation tests
identifying the blocked step and mutated gene in the pathway
only supplementing with substrates _________ of the blocked step in the pathway will rescue the defect
downstream
+ = yes, block is _________ substrate
before
