Autosomal Recessive Flashcards Preview

Biochem 4 > Autosomal Recessive > Flashcards

Flashcards in Autosomal Recessive Deck (50):
1

Angelman syndrome involves active _______ from the _______ and inactive __________ from the ________

SNRPN from father
UBE3A from mother

2

Symptoms of hurler syndrome

Progressive intellectual disability, skeletal abnormalities, short stature, corneal clouding, and course facial features

3

Diseases with delayed age of onset can reduce

Natural selection against the disease

4

Example of a heterogenous disease

Osteogenesis imperfecta col1A1 gene on chromosome 17 or chromosome 7

5

Hereditary hemochromatosis treatment

Bloodletting

6

The loss of SNRPN can result in:

Prader-Willi syndrome

7

The hardy-Weinberg equation is used when ____________ is unavailable

Family (individual) history is available

8

Hurler syndrome is a ______________ disease

Autosomal recessive

9

P^2 =

Homozygous frequency

10

Q^2=

Homozygous frequency

11

It is estimated that each person carries five recessive genes in the heterozygous form that would result in lethal phenotype if they were present in a homozygous state. This is called:

Genetic burden

12

Treatment of hurler syndrome

Targeted enzyme replacement therapy, hematopoietic stem cell transplant

13

Penetrance versus variable expression

Penetrance = did inherent, did NOT express

Variable expression = did inherent, did express in some way

14

Imprinting involves:

Methylation of specific nucleotides in the DNA and generally transcriptionally silences the gene

15

When an individual consists of more than one distinct population in eggs or sperm is called

Germaine mosaicism

16

What type of disorder is hurler syndrome?

Mucopolysacharidosis, a lysosomal storage disorder

17

The hardy-weinberg principle states that the frequency of ______ in a population is mathematically related to the frequency of _________ in a population

Alleles
Genotypes

18

HFE protein function

Detecting the amount of iron in the body and regulates the production of hepcidin, which influences iron absorption and release

19

A heterogeneous disease is one where mutations:

At different gene loci can produce the same disease phenotype

20

The hardy-weinberg principle equation is used most commonly for determining the likelihood that an individual is

Carrying a particular recessive disease allele

21

Reproduction among family members is referred to as:

Consanguinity

22

How could one with the genotype of retinoblastoma (RB1) not present with the disease?

Reduced penetrance- manifesting a retinoblastoma usually requires a second mutation that inactivated the other RB1 gene allele, 10% of those with the mutant genotype will not develop the disease

23

Anticipation in inheritance involves:

An earlier age of onset and/or more severe expression in more recent generations of a pedigree due to repeat expansions

24

Most common cause of death among those with untreated hemochromatosis

Cardiac failure

25

2pq =

Heterozygous frequency

26

Example of a disease that can display anticipation

Myotonic dystrophy
Fragile X
Huntington disease

27

Gene that Hurler syndrome effects

A-L-iduronidase

(A= alpha)

28

Hereditary Hemochromatosis specific gene mutation

Single missense mutation

29

Myotonic dystrophy specific gene mutation

DMPK gene- expansion of a trinucleotide repeat (CTG) in the 3’ untranslated portion of the gene

30

Hereditary Hemochromatosis is a _______________ disease

Autosomal recessive

31

The cause of anticipation is believed to be due to

Slippage of DNA polymerase during DNA replication leading to trinucleotide expansion

32

Germaine mosaicism involves a mutation:

Affected all or some of the germ cells in the ovaries or testes, but not enough of their somatic tissue to produce a phenotype in that parents

33

Hereditary Hemochromatosis effects which gene

HFE (high iron)

34

A recessive disease can be passed ________ through generations

Silently

35

Founder Effect:

Intermarriage within small communities can lead to many individuals carrying the same recessive mutations from the founders

36

UBE3A gene function

Ubiquitin-mediated protein degradation, strongly in the brain (cognition)

37

Penetrate refers to:

The proportion of individuals carrying a particular genotype that also express the associated phenotype

38

Prader-Willi syndrome involves active _________ from the ________ and inactive _________ from the _________

UBE3A from the mother
SNRPN from the father

39

_________ is present more often in pedigrees involving autosomal recessive diseases, especially rare diseased

Consanguinity

40

Why are males more commonly affected in hereditary hemochromatosis than females?

Delayed onset of disease (~30 years old), delayed further in women due to menstruation blood loss

41

Hurler syndome results in the

Buildup of glycosaminoglycan in lysosomes

42

On average, _____ of the offspring of makings between two heterozygous carriers will be affected with the autosomal recessive disease

1/4

43

Examples of pleiotropy

Cystic fibrosis, Marfan syndrome, NF1

44

Loss of UBE3A gene is associated with

Angelman syndrome

45

A _______ gene is one that exerts its effects on multiple aspects of physiology or anatomy

Pleiotropic

46

When does re-imprinting occur?

During opogenesis or spermatogenesis

47

Many recessive diseases involves mutations in genes that encode for

Enzymes

48

Osteogenesis imperfecta can be a __________ disease

Germline mosaic autosomal dominant

49

When two or more siblings are affected with an autosomal DOMINANT disease, but both parents are unaffected, ________ should be considered

Germline mosaicism of one of the parents

50

SNRPN gene function

Small nuclear riboprotein expressed in the brain