vocab Flashcards
penetrance
the P that disease will appear in an individual when disease allele is present
pleiotropy
one gene has many functions
maternal effect
mother’s genotype determines offspring’s phenotype rather than offspring’s genotye
allelic series
collections of variants that lead to a gradation of possible phenotypes
or
a wild type allele and all the mutant alleles of a gene that appear in a real population
heterogeneity
different mutations - same phenotype
allelic heterogeneity
mutations in same gene
locus heterogeneity
mutations in different gene
expressivity
range of symptoms that are possible
haplotype
combination of alleles present on same chromosome homolog
polygenic disease
multiple genes cause disease through combined action of disease alleles
quantitative trait loci
genes with major contributions to phenotype
transgenic rescue
add wild type allele to mutatnt phenotype disappear
knock-in
generate same sequence change in wild type mice and induce same phenotype
epigenetics
the study of heritable changes that occur without a modification in DNA sequence of the genes
canonical imprinting event
parent-of-origin specific DNA methylation - primary imprint marker that directly or indirectly controls most imprinted genes
complementation test
cross mutants to each other to see if they are in the same gene or different genes
loss of function mutation
mutation production of no or less proteins or a protein with reduced or no activity
gain of function mutation
mutation production of more proteins or an extended expression pattern (new time and or place), or a protein with an increased activity or new function
amorph
deletion / none
hypomorph
reduced function
antimorph
antagonistic (but LOF morph)
hypermorph
increased function
neomorph
novel
exons
coding regions
introns
non coding regions
COI
construct of interest
transgene
exogenous gene added into experimental system that can be expressed under its own promoter or a different promoter
knock out
delete a gene/promoter or a critical portion of it
knock down
delete a small portion of gene / promoter
knock in
add construct to genome
knock down marker
replaces a small part of the gene / promoter
knock out marker
replaces all or a great part of the endogenous gene / promoter
knock in marker
DNA is fused to a marker
HDR
homology directed repair
phenocopy effects
effects comparable to mutant phenotypes but not due to mutations
phenocopy
environmental induced - non heriditary phenotype (identical to genotype determined phenotype of another individual)
haploinsufficiency
dominant phenotype in diploid organism that are heterozygous for LOF allele
heteroallelic combination
presence of two different mutant alleles at the same locus
epistasis
one mutation masks the phenotype of the other mutation
mutations arise by
deficiencies of gene through loss of chromosome region or at breakpoints of inversions or translocations
balancer chromosomes
keep homozygous lethal or sterile mutations from being lost in a population (they are homozyous too and have a marker)
saturated genetic screen
uncover every gene that is involved in a particular phenotype in a given species
synergistic enhancement
more than addition of two phenotypes
universally conserved genes
those that can be found in all organisms
synteny
conservation of blocks of order within two sets of chromosomes that are being compared with each other
or
preserved order of genes on chromosomes of related species which results from descent from common ancester
fitness
probable genetic contribution of an individual to succeeding generations
oligos
oligonucleotides - short single strands of synthetic DNA or RNA
dominance
manifestation of how the alleles of a single gene interact in the heterozygote
haplosufficient
one copy of the wild type allele (P) is enough to carry out the function
auxotrophic mutants
cannot syntehsize cellular components from inorganic nutrients - complex nutrients need to be supplied in order for the cell to grow
suppressor
mutant allele of a gene that reverses the effect of a mutation in another gene
hypostatic
the overriden mutation in epistatic interactions
negative/antagonistic epistasis
Occurs when the two-locus epistatic interaction provides a combined fitness that is smaller than the simple sum of each of their own
positive/synergistic epistasis
Occurs when the two-locus epistatic interaction enhance the fitness of the individual more than the simple sum of each of their own
synthetic lethality
two genes have a synthetic lethal relationship if mutants in either gene are viable but the double mutation is lethal
complementation test
checking if mutants are at the same allelic locus
Tandem duplications
: duplicated regions are located adjacent to each other
Insertional duplication
extra copies are located somewhere else in the genome
Segmental duplications
: big duplication units ranging from 10 to 50kB - most of this duplication are dispersed but some may be in tandem
duplication loop (meiosis)
failure of pairing between the normal segment of chromosome and its corresponding homolog duplicated segment
CNV
copy number variation - human differs in the number of copies of parts of individual genes, whole genes, or gene clusters
orthologs
genes inherited from a common ancester (same locus, different species)
paralogs
genes arose from duplication events - at different genetic loci in the same organism
macrosynteny
larger ranges relationships
microsynteny
metabolic clusters of similarity
genetic redundancy
implies that two or more genes carry out the same biological function and that a mutation in one of these genes has little or not effect on the overall phenotype - since the other would function as a back up copy
neo-functionalization
when a gene acquires a new function after a gene duplication event
subfunctionalization
neutral mutation process in which each paralog retains a subset of its original ancestral function
Aneuploidy
: changes in parts of chromosome set
Euploidy (aberrant)
: organisms that have multiples of the normal chromosome set
nullisomy
monosomy
disomy
trisomy
2n-2
2n-1
n+1
2n+1
Gene balance
: the majority of proteins function in complexes
ways chromosomal structure can be altered (4)
deletion
duplication
inversion
translocation
paracentric inversions
do not involve the centromere (switch i think - like BC is normal, CB = paracentric)
pericentric inversions
involve the centromere
Intragenic deletion:
small deletions within a gene
Usually inactivate the gene and have same effects than other null mutations
Multigenic deletions:
several genes are missing
More severe consequences: even heterozygote for such deletions may not survive
Psuedodominance :
recessive alleles seem to show dominance bc of deletion of dominant alleles
Deletions in meiosis :
failure of pairing between the normal segment of chromosome and its corresponding homolog deleted segment
deletion loop
Autopolyploidy:
multiple chromosome sets originated from same species - intraspecific
Allopolyploidy:
multiple chromosome sets originated from different species - ineterspecific
Cell non-autonomous :
gene product is not required in cells in which it is expressed
Cell autonomous :
gene product is required in cells in which it is expressed
