Flashcards in Genetics II Deck (61):
Regarding the tri nucleotide repeat associated with Huntington's disease, it is a...
CAG repeat that occurs in the Exon
CAG repeat occurring in the Exon
What complex in the ETC (respiratory chain of the mitochondria) does NOT contain Mitochondrial DNA?
If a couple both expresses Achondroplasia, what is the chance their offspring will have the lethal form of the gene?
*Both are Heterozygous
Amelogenesia imperfecta with mutation p.Trp153.
What does this indicate?
Stop Codon was Created
What kind of mutation is this?
If a woman is a carrier for sickle cell and her husband is not, what has happened if her son expresses the trait?
Maternal MII error
*MII will essentially double the error
The repeating CCG expansion of the 5' UTR found in Fragile X Syndrome have over _____ repeats in affected individuals.
When over this number, _______ causes promoter modification and the cessation of RNA production
Autosomal Dominant disorders rarely have what mechanism of disease?
What are 3 mechanisms seen in Autosomal dominant diseases?
Loss of Function
Dominant negative, Gain of Function, Haploinsufficiency
Type 1 Osteogenesis imperfecta W/O Dentinogenesis is due to what molecular mechanism?
Type 1 Osteogenesis imperfecta WITH Dentinogenesis is due to what molecular mechanism?
Cystic Fibrosis has different mutations in the same gene giving the same clinical phenotype - what is this called?
Different mutations in different genes resulting in the same clinical phenotype is called...
CGG repeat in the non-coding 5'UTR:
CAG repeat in the 1st exon:
GAA repeat in the intron:
CTG repeat in the non-coding 3'UTR:
CGG repeat in the non-coding 5'UTR
CAG repeat in the 1st Exon
GAA repeat in the Intron
CTG repeat in the non-coding 3'UTR
What is the inheritance pattern for Achondroplasia?
*Fibroblast Growth Factor Receptror 3
_____% of individuals affected with Achondroplasia are de novo mutations on the _______ chromosome
The majority of individuals affected with Achondroplasia have a ______ to ______ substitution at codon 380.
99% of Achondroplasia is a ___ to ____ transition (purine for purine
1% of Achondroplasia is a ___ to ____ transversion (purine to pyrimidine)
G to A
G to C
Mutations causing Achondroplasia can cause an alteration of restriction sites leading to shorter DNA fragments
Mutations causing Achondroplasia can lead to "gain of function" - new or enhanced function of the gene
How is Achondroplasia diagnosed?
Huntington's disease is what type?
The age of onset changing in a disease indicates what?
Differential inheritance from mother or father indicates what?
Huntington's exhibits both Anticipation and Imprinting:
If No band is visible in Fragile X testing, the male is either ______ or ______.
Full mutation carrier
If someone has inherited a mutant allele but isn't expressing the phenotype, this may be an example of...
Penetrance (or non-penetrance)
If someone has inherited a mutant allele and may express the trait to variable degrees (different severity), this is an example of...
The increased severity and/or decreased age of onset of disease with successive generations is...
What reflects an increased number of repeats passed from generation to generation?
What is the differential modification and expression of alleles of genes depending on the Sex of the parent of origin?
(it matters who gives you what)
Prader-Willi and Angleman are best examples of what?
How many human genes have been discovered that show Imprinting expression?
Inheritance of 2 copies of a gene/chromosome from one parent is called what?
This has implications for what kind of disorders?
Recessive and Imprinted disorders
Fragile X testing, 60-200 copies is...
Fragile X testing, over 230 copies is...
Full mutation carrier
A PCR test for Fragile X will only detect up to 100 copies, if someone has the mutation, what test will confirm?
What type of genetics has a high mutation rate, limited proofreading/repair, and lack of protective histones?
Define MItochondrial Heteroplasmy:
Both wildtype and mutant mito DNA
What is the Threshold Effect of Mitochondrial DNA?
Certain min. number of mutant proteins must be present before Expression occurs
Mitotic Segregation occurs in Mitochondrial genetics
* = stop
either deletion or duplication has occurred, now there's a Stop codon
De Novo mutation on Mom's allele:
Achondroplasia detected by:
PCR restriction detection
Achondroplasia AA consequence:
Penetrance is binary
Either are or aren't penetrant
Variable expressivity is a function of penetrance
What needs to occur for Uniparental Disomy to take effect?
Must kick out other paren't chromosome
Mitochondrial Heteroplasmy =
wildtype and mutant DNA
Mitochondrial DNA has bigger mutation rate because no histones, no proofreading, and is at a site of radical oxidative formation
Beginning with a single DNA strand, how many cycles of PCR = 1 million copies