General,Renal,Cardiac,Endocrine

Question 1

Function of Messenger RNA (mRNA).

Answer 1

Translates information in DNA into Amino Acid sequences (PROTEINS)

Question 2

Function of Ribosomal RNA (rRNA).

Answer 2

Structural and catalytic role in ribosomes

Question 3

Function of MicroRNAs (miRNA).

Answer 3

Short fragments that regulate mRNA levels and therefore PROTEIN expression.

Question 4

What 2 types of RNA make up heterogenous nuclear RNA (hnRNA)?

Answer 4

miRNA and mRNA

Question 5

Function of Transfer RNA (tRNA).

Answer 5

Delivers specific Amino Acids to the ribosome for addition to a growing peptide chain.

Question 6

What catalyzes the formation of a phosphodiester bone in 5’ to 3’ direction?

Answer 6

Polymerase

Question 7

What catalyzes the formation of the phosphodiester bonds between adjacent ends of nucleotide chain?

Answer 7

Ligase

Question 8

What catalyzes cleavage of phosphodiester bonds?

Answer 8

Nuclease

Question 9

Which nucleotide is most often methylated in silenced DNA?

Answer 9

Cytosine

• Methylation of nucleotides affects cytosine moieties located within cytosine-phosphate-guanine (CpG) islands, This results in decreased DNA transcription in adjacent genes.
• The degree of silencing correlates with the number of methylated nucleotides.
• Forms the bases for IMPRINTING

Question 10

Histone Acetylation function.

Answer 10

“loosens” the histone -> INCREASED DNA transcription.

Question 11

What occurs in the S phase of cell cycle?

Answer 11

DNA replication

*Is “semiconservative”

Question 12

What unwinds the double helix in S phase?

Answer 12

• DNA helicase

- DNA topoisomerase

Question 13

When does Nondisjunction most commonly occur?

Answer 13

Meiosis I, but can occur during Meiosis II and results in aneuploidy

Question 14

What is a polymorphism?

Answer 14

Mutation that is not deleterious and is present in AT LEAST 1% of population.

Question 15

What are the 5 classes of mutations?

Answer 15

• Point mutations
• Insertion mutations
• Deletion mutations
• Inversions
• Translocations

Question 16

What are the 5 sublasses of a Point Mutation?

Answer 16

• Nonsense
• Missense
• Silent
• Splice
• Frameshift

Question 17

Define Nonsense mutation.

Answer 17

Changes codon into a STOP CODON -> Premature truncation of translation.

Question 18

Define Missense mutation.

Answer 18

Changes in AA sequence

Question 19

Define Silent mutation.

Answer 19

Change in the Nucleic Acid sequence but does NOT result in the production of a stop codon or different AA.

Question 20

Define Splice mutation.

Answer 20

Affects the mRNA splice site

Question 21

Define Frameshift mutations.

Answer 21

Change in the reading frame of the ribosome in translation.

Question 22

What is the structure of nucleosome?

Answer 22

Octamer of positively charged histone proteins.
-2 each of H2A, H2B, H3, H4

Wrapped around this is 146 bases of DNA (which has negative charge)

Question 23

Each nucleosome is linked to the next by what?

Answer 23

H1 (linker histone)

Question 24

What is the shortest chromosome?

Answer 24

21

Question 25

How are chromosomes classified?

Answer 25

by the location of the Centromere

Question 26

In Karyotyping, dividing cells are arrested in what phase of mitosis?

Answer 26

Metaphase

Question 27

In G banding (Karyotyping), which areas stain more intensely (A-T rich or G-C rich)?

Answer 27

A-T rich

Question 28

How can purity of DNA be assessed, and what ratio is considered to be relatively pure?

Answer 28

- Ratio of absorbance at 260 nm to 280 nm | - <1.8 is relatively pure

Question 29

Southern Blot

Answer 29

DNA

Question 30

Northern Blot

Answer 30

RNA

Question 31

Western Blot

Answer 31

Protein

Question 32

What inheritance pattern affects males and females equally and often skips a generation?

Answer 32

Autosomal Recessive

Question 33

Triad of Alport syndrome. (typical presenting symptom)

Answer 33

- Glomerulonephritis - Sensorineural Hearing loss - Ocular lesions (asymptomatic hematuria)

Question 34

What is inheritance pattern in Alport syndrome?

Answer 34

X-linked recessive | carrier females often manifest asymptomatic hematuri

Question 35

Mutation in Alport syndrome?

Answer 35

COL4A5 gene on Xp22.3 encodes a5 chain on type IV collagen

Question 36

Autosomal Dominant disorders generally involve genes that encode for what type of proteins?

Answer 36

- Structural proteins - Receptor proteins - Transmembrane proteins

Question 37

Autosomal Recessive disorders generally involve genes that encode for what?

Answer 37

Enzymes

Question 38

Mutation in Autosomal Recessive Polycystic Kidney Disease (ARPKD).

Answer 38

PKHD1 gene on chr6p

Question 39

ARPKD manifestations.

Answer 39

Manifest in utero - oligohydramnios - pulmonary hypoplasia

Question 40

Autosomal Dominant Polycystic Disease (ADPKD) MC mutation.

Answer 40

PKD1 on chr16p13 (85%) (1:500 live births) *100% penetrance by age 50

Question 41

What are the typical presenting symptoms in ADPKD?

Answer 41

- Hypertension | - Isothenuria

Question 42

Other manifestations associated with ADPKD?

Answer 42

- Hepatic involvement - Mitral Valve Prolapse - Pancreatic cysts - Intracranial Berry aneuryms

Question 43

Inheritance in Cystic Renal Dysplasia (aka Multicystic Dysplastic Kidney).

Answer 43

``` A noninherited (SPORADIC) disorder -may result from in utero ureteral obstruction ```

Question 44

What syndrome is associated with Cystic Renal Dysplasia?

Answer 44

Meckel-Gruber syndrome

Question 45

Features of Meckel-Gruber Syndrome

Answer 45

- Kidney disease - polydactyl - occipital encephalocele

Question 46

Gene involved in X-linked Dilated cardiomyopathy.

Answer 46

Dystrophin gene (same in Dechenne and Becker muscular dystrophy)

Question 47

MC gene involved in AD Dilated Cardiomyopathy.

Answer 47

MYH7 gene | -Beta-myosin Heavy chain

Question 48

Inheritance and Gene involved in Hypertrophic Cardiomyopathy.

Answer 48

- Autosomal Dominant | - MYH7 gene

Question 49

MC mutation in Hypertrophic Cardiomyopathy

Answer 49

R403Q on MYH7

Question 50

Noonan syndrome gene mutation.

Answer 50

PTPN11 (single gene mutation)

Question 51

Noonan syndrome features.

Answer 51

Right sided Heart defects: - Pulmonary Stenosis (MC) - Hypertrophic cardiomyopathy (2nd MC)

Question 52

Alagille syndrome gene mutation.

Answer 52

JAG1 (single gene mutation) | -Autosomal Dominant

Question 53

Alagille syndrome features.

Answer 53

``` Alagille syndrome (AKA arteriohepatic dysplasia) -Bile Duct paucity Also effects blood vessels and heart -Pulmonary artery stenosis -Tetralogy, ASD, VSD, AS, coarctation ```

Question 54

Turner syndrome MC heart defect.

Answer 54

-Bicuspid Aortic Valve 2nd MC: Coarctation

Question 55

Which steroid is elevated (serum) in ALL forms of Congenital Adrenal Hyperplasia (CAH)?

Answer 55

17-Hydroxyprogesterone (17-OHP)

Question 56

What is the MCC of Congenital Adrenal Hyperplasia?

Answer 56

21-hydroxylase deficiency

Question 57

What gene encodes 21-hydroxylase?

Answer 57

CYP21 on chr16 within HLA locus

Question 58

What is the 2nd MCC of CAH?

Answer 58

11-hydroxylase deficiency (North African Jews)

Question 59

What gene and chromosome is ass. w/ Androgen Insensitivity Syndrome?

Answer 59

- Androgen Receptor - X chromosome (X-linked recessive disorder that affects genotypic males (46XY))

Question 60

What gene influences the genital primordium to develop into Testes?

Answer 60

SRY gene on Y chromosome

Question 61

Kallman syndrome features.

Answer 61

- Hypogonadotropic hypogonadism | - Anosmia

Question 62

Kallman syndrome mutation and MC hormane deficiency.

Answer 62

- KAL1 gene on Xp22.3 | - Growth Hormone deficiency

Question 63

McCune-Albright Syndrome gene mutation.

Answer 63

GNAS1 (gain of function mutation)

Question 64

T/F: McCune-Albright syndrome are somatic mosaics.

Answer 64

True -Germline mutation incompatible with life

Question 65

McCune-Albright syndrome features.

Answer 65

- Fibrous Dysplasia - Cafe-au-lait spots - Precocious puberty - Endocrine abnormalities

Question 66

HLAs associated with DM1

Answer 66

HLA-DR3 HLA-DR4 - heterozygotes (2-3X Risk) - homozygotes (10X Risk)