Finals

Question 1

Which of the following is an autosomal recessive disorder?

a. Defect of nucleotide excision repair of XPC subunit
b. Mutation in uroporphyrinogen decarboxylase gene.
c. Mutation in Fragile X mental retardation 1 gene.
d. Defect in collagen type IV alpha 5 chain gene.

Answer 1

Defect of nucleotide excision repair of XPC subunit

Question 2

Which of the following is an autosomal dominant disorder?

a. Mutation in fibroblast growth factor receptor 3 gene.
b. Mutation in hexosaminidase subunit alpha gene.
c. Mutation in hypoxanthine phosphoribosyltransferase 1 gene
d. Mutation in phosphate regulating endopeptidase homolog gene.

Answer 2

Mutation in fibroblast growth factor receptor 3 gene.

Question 3

This is a type of brachydactyly resulting in the shortening of one or more metacarpals/metatarsals.

Answer 3

Type E

Question 4

The following are not true about familial hypercholesterolemia, except?

a. Genetic testing is available to check for mutations in the cell-surface membrane for the cholesterol to be absorbed.
b. A mutation in only one copy of the gene is enough to cause the disease.
c. A person having two FH-causing mutations in both copies of the same gene which will have less levels of cholesterol, however can still have heart attacks in childhood.
d. If either the mother or father has a mutation that causes FH, they have 25% chance of passing it to the offspring.

Answer 4

A mutation in only one copy of the gene is enough to cause the disease.

Question 5

Which is true about the basis for inherited diseases?

a. Mutations are rare events; they may arise in one population but not another.
b. Each population is exposed to its own unique set of environmental conditions that may influence the prevalence of a given allele.
c. Genetic diseases cannot spread from person to person.
d. All of the choices are true.

Answer 5

d. All of the choices are true.

Question 6

This disease is characterized by shortened long bones, rhizomelic shortening and a trident hand.

Answer 6

Dwarfism

Question 7

Malignant phenylketonuria results from biallelic mutations in what gene?

a. GCH1 gene
b. PCC1 gene
c. PTR gene
d. QDDR gene

Answer 7

GCH1 gene

Question 8

Which of the following statements refer to Sickle Cell Anemia?

I. There’s a base point mutation leading to the substitution of amino acid glutamic acid to valine at the 5th position of the alpha chain of hemoglobin S.

II. Signs and symptoms of the diseases usually begin in early childhood including low red blood cell count and repeated infections.

III. When each parent has one sickle cell gene and one normal gene, each child has a 25% chance of having the disease.

IV. Considering that only one parent has the disease, each child will inherit one sickle cell gene from that parent and will have the sickle cell trait.

V. The biggest risk factor for inheriting sickle cell anemia is a family history of the disease.

Answer 8

II, IV and V are correct

Question 9

This disease is characterized by an abnormality in dentition, arthralgia, and cutaneous photosensitivity.

Answer 9

Xeroderma Pigmentosum

Question 10

Which of the following is/are the risk factor/s for X-linked hypophosphatemia?

a. There’s low phosphate level leading to abnormal bone development.
b. Inadequate dietary of Vitamin D causing low calcium levels.
c. Both A and B.
d. Neither of A and B.

Answer 10

Both A and B.

Question 11

This gives you an orange sand diaper.

Answer 11

Lesch-Nyhan Syndrome

Question 12

People with Tay-Sachs disease inherit one mutation from each of their parents. When 2 carriers of an autosomal recessive disease have children, each child has?

I. 1 in 4 chance to have the disease

II. 1 in 2 chance to be an unaffected carrier like each parent

III. 1 in 4 chance to be unaffected and not a carrier

Answer 12

I, II and III are correct

Question 13

Mutation in the cystic fibrosis transmembrane regulator gene leads to, except:

a. Dehydration
b. Abnormally salty sweat
c. Thick mucus secretions
d. Decrease Viscosity of sections

Answer 13

d. Decrease Viscosity of sections

Question 14

Porphyria results from defects in porphyrins due to mutations of which of the following genes?

a. Hydroxymethylbilane synthetase gene
b. Uroporphyrinogen II synthase gene
c. Coproporphyrinogen oxidase gene
d. Uroporphyrinogen carboxylase gene

Answer 14

Coproporphyrinogen oxidase gene

Question 15

A form of tay-sachs disease distinguished by behavioral problems, gradual loss of skills and respiratory infections.

Answer 15

Juvenile

Question 16

Marie and Paul have recently suspected their son, Pat, might have a mutation in a certain gene containing a section of DNA CGG triplet repeat. For this reason, they would like their family to undergo genetic testing. Their daughter, Katie, shows no symptoms of the disease.

The following statement is true about the case above?

I. This is a genetic condition involving changes in the part of the X chromosome.

II. This disease may have a significant cause of developmental problems including cognitive impairment.

III. This is an X-linked recessive disorder with its treatment is based on the symptoms.

IV. Men with premutation are at risk for the CGG repeats over 200 repeats when passing this gene to the offspring.

Answer 16

I, II

Question 17

Patient X is 3 years old and 2 months, male, came to the nearest hospital with a complaint of a bleeding tongue. The patient has been presenting his symptoms for the past 24 hours and presented to the hospital with continuous bleeding from his tongue until a few hours before reached the hospital. The patient had accidentally bitten his tongue which led to profuse bleeding from the dorsal surface of the tongue. No other bruising or active bleeding was noticed except extensive bruising over his left scapular area and the presence of hematoma on the chin and right elbow with active bleeding in the past 3 days. Pedigree analysis revealed below:

Which of the following statement is true in the case above?

I. Female must be homozygous in the gene to be affected.

II. This patient might have a lack of clotting factor VIII causing weak platelet plug formation.

III. This condition is an X-linked dominant disorder.

IV. Mild form of this disease may not be diagnosed until they bleed more than normal after a major injury.

Answer 17

I, II, IV

Question 18

This pertains to the location of a gene on a chromosome.

Answer 18

Locus

Question 19

A karyotype test

I. Determine the size of the chromosome

II. Determine the shape of the chromosome

III. Determine the number of chromosomes

Answer 19

I, II, III

Question 20

Application of karyotyping analysis

I. Diagnose a fetus for a genetic disorder

II. Diagnose a genetic disorder in utero

Answer 20

Both

Question 21

Karyotype 45, XO represents:

Answer 21

Female with Turner syndrome

Question 22

Karyotype 47, XX, +13 represents:

Answer 22

Female with Patau syndrome

Question 23

This is the transfer of a chromosome or a segment of it to a non-homologous chromosome.

Answer 23

Translocation

Question 24

It is a nucleic acid that can be labeled with a marker and will hybridize with another nucleic acid on the basis of base complementarity, which allows the identification and quantification of target genes.

Answer 24

Probe

Question 25

In FISH, the “in situ” literally means what?

Answer 25

In position

Question 26

In karyotyping, chromosomes are arranged into homologous pairs based on the following, except:

a. Banding patterns
b. Diameter of the p and q arm
c. Length and size
d. Location of the centromere

Answer 26

Diameter of the p and q arm

Question 27

Taq DNA polymerase is used for PCR because

Answer 27

This polymerase can withstand high temperatures used in PCR.

Question 28

What is the correct order of steps of a PCR cycle?

Answer 28

Denaturation, annealing, extension

Question 29

In PCR, this determines the portion or segment of the DNA to be amplified

Answer 29

Primers

Question 30

In FISH analysis, probes will hybridize to another nucleic acid on the basis of:

Answer 30

Base complementarity

Question 31

How many copies of DNA are produced after 4 PCR cycles?

Answer 31

16 copies