Genetics

Question 1

Genetic Anticipation

Answer 1

Condition that presents earlier and more severe in successive generations

Question 2

Genetic Heterogeneity

Answer 2

Different Genetic mutations causing same disease

Question 3

Germline Mosaicism

Answer 3

Unaffected parents having Gametes with mutated allele that is passed to offspring

Question 4

Maternal Imprinting

Answer 4

Selective silencing of genes inherited from mother. The expression of genes are determined by information from fathers side

Question 5

Example of Genetic Anticipation

Answer 5

Myotonic Dystrophy

Question 6

Example of Genetic Hetrogeneity

Answer 6

Tuberous sclerosis

Question 7

Example of Maternal Imprinting

Answer 7

Prader-Willi Syndrome

Question 8

Stop Codons

Answer 8

UAA
UAG
UGA

Question 9

G6PD enzyme function

Answer 9

Converts glucose 6 phosphate to 6-phosphogluconate

Question 10

Down Syndrome GI Complications

Answer 10

Duodenal Atresia and Hirschsprung Disease

Question 11

Down Syndrome Malignancy

Answer 11

ALL

Question 12

Almond Shaped Eyes, Narrow Forehead, Short Stature, Obese and hypogonadism

Answer 12

Prader-Willi Syndrome

Question 13

Long Narrow Face, Prominent Forehead and chin, large everted ears

Answer 13

Fragile X Syndrome

Question 14

Flat Occiput with bilateral epicanthal folds, single palmar crease

Answer 14

Downs Syndrome

Question 15

Prominent occiput, Low set ears and small jaw

Answer 15

Edwards Syndrome

Question 16

Polydactyly, Rocker bottom feet, Cleft Lip and Cleft palate

Answer 16

Patau Syndrome

Question 17

Fragile X syndrome Trinucleotide Repeat

Answer 17

CGG

Question 18

The 5 As of Down syndrome:

Answer 18

• Advanced maternal age
• Atresia (duodenal)
• Atrioventricular septal defect
• Alzheimer disease (early onset)
• ALL

Question 19

Key Features of Kartagener’s Syndrome

Answer 19

Infertility
Recurrent Sinus Infections
Chronic Cough

Question 20

Pleiotropy

Answer 20

when one gene contributes to multiple seemingly unrelated phenotypic effects. This phenomenon explains how a single gene mutation can cause a disease affecting multiple organ systems

Question 21

Variable Expressivity

Answer 21

Two individuals can have exactly the same mutation on the same chromosome (i.e., same genotype), but show a different degree of disease manifestation and severity

Question 22

Anticipation

Answer 22

Pattern of inheritance in which the succeeding generation develops a disease with greater severity or at a younger age than the ones before

Question 23

MECP2 gene mutation

Answer 23

Rett Syndrome

Question 24

Almond Shaped eyes, Obesity and Narrow Bridge of Nose

Answer 24

Prader-Willi Syndrome

Question 25

Frontal Balding and Cataracts

Answer 25

Myotonic Dystrophy

Question 26

Trinucleotide repeat of CTG

Answer 26

Myotonic Dystrophy

Question 27

Inheritance pattern of Lesch-Nyhan syndrome

Answer 27

X-linked recessive

Question 28

Inheritance pattern of severe combined immunodeficiency (SCID)

Answer 28

Autosomal Recessive

Question 29

mutation of the tumor suppressor p53 gene located on chromosome 17

Answer 29

Li-Fraumeni syndrome

Question 30

Function of Retinoblastoma gene

Answer 30

Prevents cell-cycle progression past the G1/S checkpoint

Question 31

Lens subluxation downward and inward

Answer 31

Homocystinuria

Question 32

Lens subluxation upward and outward

Answer 32

Marfan syndrome

Question 33

maple syrup urine disease caused by

Answer 33

α-keto acid dehydrogenase deficiency

Question 34

t(14;18) translocation

Answer 34

Follicular B-cell lymphoma

Question 35

Function of α-keto acid dehydrogenase

Answer 35

Breaks down isoleucine, leucine, and valine (Branched amino acid)

Question 36

What is the role of the mRNA start codon AUG in prokaryotes in the innate immune response?

Answer 36

Codes for N-formylmethionine (fMet) → stimulate neutrophil chemotaxis

Question 37

Which ophthalmologic finding may be present in a patient with Down syndrome

Answer 37

Brushfield spots (whitish spots at the margin of the iris)

Question 38

A mutations affects male and female offspring with equal frequency, but disease often presents with varying severity even in those with the same mutation

Answer 38

Heteroplasmy

Question 39

A defect in fibrillin-1 is associated with

Answer 39

Marfan syndrome.

Question 40

Intestinal rupture Thin skin Bruising and varicosities Suggestive of

Answer 40

Vascular Ehlers-Danlos syndrome