Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
43 Cards in this Set
- Front
- Back
Mendelian Traits:
Autosomal Dominant Inheritance |
Heterozygotes express the trait
Vertical pattern of transmission from one generation to the next Transmitted by both sexes Offspring are at 50% risk Structural genes are often involved New mutations are common ( point mut more common in sperm). |
|
Incomplete penetrance
|
a trait that is not expressed in the phenotype of a gene carrier
|
|
Complete penetrance
|
genetic trait that is expressed in the phenotype
|
|
Variable expression
|
a genetic mutation associated with more than oe phenotype
Phenotypic variablity. |
|
Give an example of variable expression (phenotypic).
|
The expression of Van der Woude syndrome varies within a family: some have cleft lip, some cleft palate, others lip pits
Interfamilial variation may be due to the effect of different mutations within the same gene. |
|
Mendelian Traits:Autosomal Recessive Inheritance
|
Homozygotes express the trait
Horizontal pattern of transmission within a sibship. Transmitted by both sexes Offspring of carrier parents are at 25% risk Functional genes are often involved Ex. Sickle cell disease Consanguinity is more common |
|
Incomplete penetrance
|
a trait that is not expressed in the phenotype of a gene carrier
|
|
Complete penetrance
|
genetic trait that is expressed in the phenotype
|
|
Variable expression
|
a genetic mutation associated with more than oe phenotype
Phenotypic variablity. |
|
Give an example of variable expression (phenotypic).
|
The expression of Van der Woude syndrome varies within a family: some have cleft lip, some cleft palate, others lip pits
Interfamilial variation may be due to the effect of different mutations within the same gene. |
|
Mendelian Traits:Autosomal Recessive Inheritance
|
Homozygotes express the trait
Horizontal pattern of transmission within a sibship. Transmitted by both sexes Offspring of carrier parents are at 25% risk Functional genes are often involved Ex. Sickle cell disease Consanguinity is more common |
|
X-linked recessive inheritance: When is it lethal?
|
When transmitted by fmeales only- example Duchenne Muscular Dystrophy.
|
|
X-linked recessive inheritance: When is it not lethal?
|
WHen transmitted by both sexes- example color blindness
|
|
Anticipation
|
The phenotype becomes more severe or evident at a younger age of onset with each successive generation
Example: The triple repeat (The repeat number correlates to the severity of the disease, at meiosis can’t line up correctly). |
|
Give an example of anticipation be specific
|
The premutation for Fragile X in a normal transmitting male expands during female meiosis in his unaffected daughter to a full mutation in her affected son.
|
|
Parent of Origin Effect
|
Parent of Origin effect - The phenotype varies depending on which parent transmits the abnormal allele
|
|
How does Methylation affect gene products (parent of origin effect)?
|
Methylation patterns differ in male and female meiosis: some genes are active only when inherited from one parent (imprinting)
Ex. Only the maternal copy of the Angelman syndrome gene is active; the paternal gene is inactive. |
|
Polygenic traits
|
many genes each make a small contribution to the phenotype
Ex. Intelligence, height |
|
Multifactorial traits
|
Few genes make a major contribution to the phenotype in a permissive environment
Ex. Spina Bifida, MTHFR and folate deficiency |
|
Mosaicism
|
A mutation affects only some cells in the body with a variable phenotype
osteogenesis imperfecta Type II (lethal autosomal dominate trait) |
|
Specific Example of Chromosomal translation
|
Down Syndrom due to familial translocation
|
|
Specific example of maternal inheritance
|
Mitochondrial genome is cytoplasmic so mitochondrial defects are passed down in the egg cytoplasm from the mother to all of her children
|
|
Carrier Frequency
|
Prevalence of an altered diease gene
|
|
Founder Effect
|
higher fequency of a specific gene mutation in a populaiton founded by a small ancestral group
|
|
What percent of sibilings will be a carrier of CF of an affected brother/sister?
|
66P of siblings will be a carrier of CF of an affected brother/sister.
|
|
What do you use genome scanning techniques for?
|
To search for chromosome aberrations (differences).
|
|
What is CGH? (genetic testing)
|
Comparative Genomic Hybridiation (CGH). Used to determine deletion or insertion.
|
|
Start Codon
|
AUG
|
|
Why are splice site important?
|
They tell the the intron will be cleaved out, if there is a mutation on an intron will get the wrong exons put to other aka wrong mRNA.
|
|
Define: Polymorphism
|
DNA changes that do NOT alter the protein function.
|
|
Define: Mutation
|
Change in normal base pair and ALTERS protein function.
|
|
Missense Mutation
|
Changes to a codon cause a another AA to be added.
|
|
Nonsense
|
Change AA codon to a STOP codon
|
|
Frameshift
|
insertion/deletion of base pairs cause a STOP codon downstream
|
|
What part of blood do you use for DNA testing?
|
WBC
|
|
Linkage Analysis
|
Looks for DNA markers near gene of interest. Need multiple family members DNA aalysis.
|
|
ASO Hybridization
|
Allele Specific Oligonucleotide Hybridization.
1) Amplify DNA 2) Add radiolabeled normal probes and known mutant DNA 3) Observe that the mutant matches up with one ( on paper dot mutatnt will match up with known) |
|
PCR
|
Polymerase Chain Reaction (PCR). Use 2 primers amplify
|
|
Single Strand Conformational Polymorphism (SSCP)
|
Denature
Put in Gel Look for difference in movement compaired to normal. Checking shape! |
|
Heteroduplex Analysis (CSGE)
|
Amplify
Denature Single Strand Cold Re-nature (can see the extra nucleotides, due to genetic problem). See that some bands are different on gel. |
|
DNA Sequencing
|
Read Left to right and then top to bottom
|
|
Protein Truncation Assay
|
DNA --> RNA
RNA --> Protein Protein put on gel. See different mobility on getl for the truncated one! |
|
What is the major cause of morbidity and mortality in infants?
|
Congenital anomalies
|