Review Slides- 10/1/21 Flashcards
Amniocentesis
-15+ weeks
1/300-1/500 risk for miscarriage
detects ~98% of open neural tube defects
Types of testing on CVS and Amniocentesis (4)
- FISH and karyotype
- Microarray testing
- Alpha-fetoprotein on amniocentesis
- Targeted testing for single gene (family specific)
Deletion
he or more DNA pair lost
Insertion
One or more DNA pair added
Frameshift mutations
When there is a deletion or insertion in a gene that isn’t a multiple of 3
Null mutation
Loss of function, but the normal allele enough to compensate. Classic autosomal recessive
Haploinsufficiency
Homozygotes more serious than heterozygotes, dominant pattern
Dominant negative
One abnormal allele is enough to show trait, osteogenesis imperfecta
Short tandem repeat polymorphism (STRP) testing
-Short tandem reacts are highly variable
-analysis of a small number of STRP’s allows for accurate testing
Used for:
-forensics
-Paterity/maternity
-Twin
Pathogenicity locus
Region of genes that code for pathogenic protein
Transcription unit
A sequence of DNA bases that is transcribed to give a single discrete complementary RNA
Oberon
When multiple genes are on the same transcription unit
Holin
A protein in C diff that allows the toxin to exit the cell
Promotor site
A special region of DNA where RNA polymerase binds for the purpose of initiating transcription
Termination site
A site within DNA or RNA product, at which RNA synthesis stops
Subunits of DNA dependent RNA polymerase
Beta, Beta’, Alpha, sigma
Rifamycin
blocks elongation, used for TB
Lipiarmycins
Blocks initiation, used for C. Diff, extremely specific to C. Diff
Two forms of RNA polymerase
holoenzyme and core enzyme, holoenzyme includes sigma and core enzyme does not
Role of sigma subunit (3)
- Causes stable binding at promotor
- Reduces binding at non-promotor sites
- Removal of sigma allows escape from the promotor
Factor independent termination
Factor termination site that is encoded in the DN Asequence, dryad symmetry
Factor dependent termination
Rho factor binds to a site in the RNA and causes the poly to stop and release
Generic transcription regulation
- Positive regulators bind upstream of the promotor, causing higher affinity binding
- Negative regulators overlap with promotor, preventing binding
TcdR sigma
It is a sigma factor that promotes the expression of many Tcd operons
CodY-Ile
Repress or of the Tcd genes when bound to Ile, inactive when not
TcdC
Anti-sigma factor that inactivates the sigma protein and prevents synthesis
