Genetics 2

Question 1

May be markers for diabetes or hypertension

Answer 1

single nucleotide polymorphism

Question 2

Fragile X syndrome is an example

Answer 2

trinucleotide repeat mutation

Question 3

sickle cell anemia is an example

Answer 3

point mutation

Question 4

Huntington disease and neurofibromatosis is an example of

Answer 4

autosomal dominant disorders

Question 5

Oral-Facial-Digital syndrome (OFD) type I is an example of

Answer 5

X-linked dominant

Question 6

Autosomal dominant disorder of CT due to mutation of “FBN1 gene” –> you get abnormal “fibrillin” (which is a glycoprotein necessary for normal elastic fiber production

Answer 6

Marfan syndrome

Question 7

Tall, thin body with abnormally long legs, arms, and fingers (Wolters….)
Dislocation of the eyes
Aortic aneurysm and dissection leading to heart failure and aortic rupture

Answer 7

Marfan syndrome

Question 8

collagen synthesis problem

Answer 8

ehlers-danlos syndrome

Question 9

This causes:
xanthomas of the skin
premature atherosclerosis - plaque build-up in arteries

Answer 9

hypercholesterolemia

Question 10

Mutation in the gene for the LDL receptor resulting in impaired metabolism and increased LDL cholesterol in plasma

Answer 10

hypercholesterolemia

Question 11

-normal at birth, but within 6 months elevated phenylalanine levels impair brain development and mental retardation is evident

Answer 11

Phenylketonuria

Question 12

-Screening at birth is mandatory in USA and restricting dietary phenylalanine intake will prevent mental retardation

Answer 12

Phenylketonuria

Question 13

-accumulation of insoluble large molecules in macrophanges with hepatosplenomegaly

Answer 13

Lysosomal Storage Diseases

Question 14

frequent CNS involvement, mental retardation, and/or early death

Answer 14

Lysosomal Storage Diseases

Question 15

-associated with increased maternal age

45 years old - 1:25

Answer 15

Trisomy 21 aka Down Syndrome:

Question 16

you get increased susceptibility to infection like periodontal disease in childhood

Answer 16

Trisomy 21 aka Down Syndrome:

Question 17

large tongue and epicanthic folds

Answer 17

Trisomy 21 aka Down Syndrome:

Question 18

this occurs due to meiotic non-disjunction of chromosome 21 during formation of the ovum

Answer 18

Trisomy 21 aka Down Syndrome:

Question 19

defined as male hypogonadism that develops when there are 2 chromosomes and one or more Y chromosomes

Answer 19

Klinefelter Syndrome

Question 20

increased length of lower limbs, reduced body hair, gynecomastia - most common reason for hypogonadism (swelling of breasts in males)

Answer 20

Klinefelter Syndrome

Question 21

short stature, webbed neck, low post hairline, high-arched palate. primary amenorrhea (absence of menstruation)

Answer 21

Turner Syndrome

Question 22

due to partial or complete absence of the X chromosomes

Answer 22

Turner Syndrome

Question 23

used fliorescent dye-labeled probes that recognize sequences specific to chromosomal regions

Answer 23

fluorescence in situ hybridization

Question 24

uses different colored dyes attached to large segments of the test DNA and normal DNA, followed by hybridization

Answer 24

comparative genomic hybridization

Question 25

1. PCR analysis - amplify the DNA in question
2. compare the order of nucleotides of this DNA to a normal DNA sequence
3. use restriction enzymes and run the segments on gel electrophoresis, compare to normal DNA

Answer 25

molecular diagnosis of genetic disorders