Random Flashcards
(91 cards)
You are evaluating a 4 year-old girl referred from a nutritionist for severe obesity. The past medical history is notable for decreased fetal movements, severe hypotonia for the first year of life, strabismus, and mild intellectual disability. At age three-years she began to rapidly gain weight and is now obsessed with food to the point that her parents have to carefully control food in the home. Which of the following tests has the best chance of confirming the likely diagnosis?
A. Growth hormone levels B. Methylation studies of chromosome 15q11-q13
C. High resolution chromosome analysis in her father
D. Sequencing of the UBE3A gene E. FISH deletion testing for PRader Willi/Angelman Syndrome
B. Methylation studies of chromosome 15q11-q13
A 5-year-old girl presents with classic Duchenne Muscular Dystrophy, an X-linked recessive disorder. Which of the following explanations could best explain this unsual occurrence?
A. An Xp chromosomal deletion that includes the DYSTROPHIN gene (the gene mutated in Duchenne Muscular Dystrophy)
B. An unbalanced X-autosomal chromosomal translocation that transects the DYSTROPHIN gene.
C. X linked testicular feminization
D. Autosomal translocation of SRY
C. X linked testicular feminization
A pregnant woman and her husband are referred for genetic counseling regarding their risk of having a second child with Duchenne Muscular Dystrophy. There is no history of his DMD disease in her family. What is the best estimate of their risk
that this fetus will have DMD?
A. 50% B. 33% C. 25% D. 17%
D. 17%
Which of the following best describes the frequency of occurrence of a medical problem in Down Syndrome?
A. Seizures in 25%
B. Thyroid disease in 25% C. Webbed neck in 25%
D. Autism in 50%
E. Horseshoe kidneys in 50% F. Structural GI tract defects in 50%
B. Thyroid disease in 25%
Which of the following approaches have been highly successful when applied to discovery of genes involved in susceptibility to common “complex” diseases such as type 1 diabetes, asthma, coronary artery disease, and many others?
A. Candidate gene DNA sequencing analysis
B. Candidate gene association studies
C. Genomewide genetic linkage studies
D. Genomewide association studies
E. All of the above
Genomewide association studies
A man is affected with an X linked dominant disorder which has a penetrance of 60%. His wife is homozygous normal at this locus. What is the probability that his first daughter will be affected?
A. 25% B. 40% C. 50% D. 60% E. 100%
D
An African American couple comes to the clinic for counseling because the husband’s brother is affected with sickle cell anemia. Neither the husband nor wife is are anemic. The population carrier rate for heterozygotes in the African American community is approximately 1 in 12. What is the risk that this couple will have a child with sickle cell anemia
1/72
Common methylation on DNA
5- methylcytosine
if 5 methylcytosine is deaminated….
Thymine
deamination of cytosine….
uracil
Origin of replication usually rich in
A-T repeats
Origin binding proteins in eukaryotes and prokaryotes
E- ORC
P- DNAA
Helicases in P and E
E- MCM
P- DnaB
SSBPs in P and E
E- RPA
P- SSB
Common alkylation of DNA
0-6 methylguanine
O6 methylguanin->
A
Enzymes that fix 06 methylguanine
methyltransferase
CTD of Pol ___ is phosphorylated by ____ subunit of ____
II
CDK7
TFIIH
How far is the TATA box from start site?
30 bp upstream
alpha amantin is a ____ inhibitor of RNA pol
Non competitive
Aspirin inhibits ___
degradation of IKB
Strong helix formers
Alanine and leucine
Helix breakers
Proline and glycine
Prions are rich in ____
beta sheets
