Genetic Disorders

Question 0

Mechanism of microRNA in inhibiting gene expression

Answer 0

(A)mRNA cleavage

(B)preventing ribosomes fron reading it

Question 1

Single Nucleotide Polymorphism is a DNA abnormality where variations are located at single isolated nucleotide positions. This is often biallelic. What does biallelic mean?

Answer 1

One of only two choices exist at a given site within population

Question 2

True or false. Small interfering RNA and microRNA have the same mechanism

Answer 2

True

Question 3

Identify:
Photographic representation given as total number of chromosomes (arranged in decreasing length), followed by sex chromosome conplement, and then abnormalities in ascending numerical order

Answer 3

Karyotype

Question 4

True or false. All mutations manifest phenotypically

Answer 4

False

Question 5

Identify

Heritable changes in gene expression that are not caused by alterations in DNA sequence

Answer 5

Epigenetics

Question 6

Measurement of all proteins expressed in a cell/tissue

Answer 6

Proteomics

Question 7

Computer-based techniques that manage data on and analyze gene & protein expression

Answer 7

Bioinformatics

Question 8

Which is false?
A. All genetic diseases are congenital.
B. All congenital diseases are genetic.
C. Both are false
D. Both are true

Answer 8

C.

Some congenital diseases are not genetic, while some genetic diseases are not congenital.

Question 9

Mutation where a single base is deleted

Answer 9

Point mutation

Question 10

Mutation where 1-2 bases are inserted/removed

Answer 10

Frameshift mutations

Question 11

Mutations that alter the meaning of sequence of encoded protein

Answer 11

Missense mutation

Question 12

Differentiate conservative missense mutation from its non-conservative counterpart

Answer 12

Non-conservative : marked change in protein fxn

Question 13

Mutation where amino acid codon is changed to a stop codon

Answer 13

Nonsense mutation

Question 14

Mutations within noncoding sequence may lead to __

Answer 14

Marked reduction/total lack of transcription

Question 15

Mutation that is characterized by amplification of a sequence of three nucleotides

Answer 15

Trinucleotide repeat mutation

Question 16

True or false. The degree of amplification @ trinucleotide repeat mutation increases during gametogenesis

Answer 16

True

Question 17

Mutations in single genes are also known as Mendelian disorders. Why?

Answer 17

They are consistent with the Laws of Segregration & Independent Assortment

Question 18

False about autosomal dominant disorders
A. Two defective genese have to be present
B. Expressed in heterozygotes
C. Unaffected people still can transmit disease to offspring
D. On average, Equal proportion of normal and affected offpspring

Answer 18

A

One is enough.

Question 19

False about autosomal dominant disorders
A. Patients always have infected parents
B. The person may inherit it but remain phenotypically normal
C. Variable expressivity is present in people with these diseases

Answer 19

A

Mutations involving egg or sperm may cause this

Question 20

In autosomal dominant disorders, involved genes usually do not encode __

Answer 20

Enzyme proteins

Question 21

Achondroplasia: mutation in ___

Answer 21

Fibroblast growth factor receptor 3

Question 22

Direct consequences of achondroplasia

Answer 22

Abnornality of cartilage formation

Shortened bones

Question 23

Specific mutation + gene mutated @ Marfan syndrome

Answer 23

Missense mutation at gene coding for fibrillin – 1(FBN1) on 15q21.1

Question 24

Marfan syndrome : inherited disorder of __

Answer 24

Connective tissue

Question 25

What are neurofibromas?

Answer 25

Benign tunors of peripheral nerves of Schwann cell origin

Question 26

Neurofibromatosis-1 is also known as ___

Answer 26

von Recklinghausen's disease

Question 27

NF-1 is characterized by areas of dark pigmentation on skin, also known as __

Answer 27

Cafe au lait spots

Question 28

NF-1 is also characterized by pigmented lesions of the iris, aka __

Answer 28

Lisch nodules

Question 29

Familial hypercholestrolemia involes mutations in the gene encoding ____

Answer 29

LDL receptor

Question 30

Gene encoding LDL receptor is located at __

Answer 30

Short arm of chromosome 19

Question 31

False about autosomal recessive disorders A. Only one allele is enough for disorder to manifest B. Siblings may show disease C. May be a product of consanguineous marriages D. Onset is frequently early on in life

Answer 31

A You need two

Question 32

In autosomal dominant disorders, onset is frequently at adulthood. Yes or no?

Answer 32

Yes

Question 33

In sickle cell anemia, there is substitution of __ for __

Answer 33

Valine for glutamic acid residue

Question 34

In sickle cell anemia, the substitution happens at ___

Answer 34

6th position of beta globin chain

Question 35

In phenylketonuria, this enzyme is lacking. High levels of Phenylalanine are present in the blood, therefore.

Answer 35

Phenylalanine hydroxylase

Question 36

False about Y-linked disorders A. Related to spermatogenesis B. Infertile male C. May be also transmitted via the mom

Answer 36

C

Question 37

False about X-linked disorders A. Females may only be homozygous B. Lack of transmission from father to son C. Most X-linked traits are recessive

Answer 37

A Females may also be heterozygous

Question 38

Differentiate hemophilia A from hemophilia B

Answer 38

A - defect @ gene encoding for factor VIII | B - defect @ gene encoding for factor IX

Question 39

Fragile X syndrome may lead to inherited mental retardation. What kind of mutation happens here?

Answer 39

Expansion of CGG repeat @ Xq27.3 fragile site. Around 200 to 4000 repeats. Average is 29

Question 40

Identify | Diseases that are consequences of additive effects of several abnormal genese and envt factors

Answer 40

Complex multigenic disorders

Question 41

These immune cells are often used in karyotyping

Answer 41

Circulating lymphocytes

Question 42

What is a metacentric chromosome?

Answer 42

Chromosome at the center --> 4 chromatids of equal length

Question 43

What is a sub-metacentric chromosome?

Answer 43

Centromere is a little away from the center. One is slightly longer than the other.

Question 44

What is a acrocentric chromosome?

Answer 44

Centromere closer to one end. Lengths of sides are very unequal.

Question 45

What is a telocentric chromosome?

Answer 45

Centromere only at one end. One side only. Not in human cells

Question 46

What is an aneuploid chromosomal abnormality?

Answer 46

Karyotype is not exact multiple of haploid number

Question 47

What is monosomy?

Answer 47

Absence of one chromosome of homologous pair

Question 48

What is trisomy?

Answer 48

Extra copy present in normally paired chromosome

Question 49

Trisomy 21 is also known as __

Answer 49

Down Syndrome

Question 50

Most conmon cause of trisomy 21 is meiotic nondisjunction. What is meiotic nondisjunction?

Answer 50

Failure of paired chromosome to separate and move to opposite poles of the spindle at anaphase

Question 51

Trisomy 18 is also known as __

Answer 51

Edwards Syndrome

Question 52

Trisomy 13 is also known as __

Answer 52

Patau syndrome

Question 53

Cri du chat syndrome has what kind of mutation?and in what part of what chromosome?

Answer 53

Deletion of the end of the p arm @ chromosome 5

Question 54

False about Klinefelter Syndrome A. XXY B. Dahil XX, female C. Both are false

Answer 54

B Male pa rin. Infertile lang.

Question 55

False about Turner Syndrome A. XXX B. May come with primary amenorrhea C. Female hypogonadism

Answer 55

A X lang hehe

Question 56

What is Huntington disease?

Answer 56

Repeats of guanine and cytosine nucleotides that occur in coding regions

Question 57

[CHROMOSOMAL REARRANGEMENTS] What is a translocation?

Answer 57

Part of chromosome transferred to another chromosome