Genetics - First Aid USMLE Flashcards
1
Q
Modes of inheritance
What mode of Inheritance is presented here?
A
Modes of inheritance
X-linked recessive
2
Q
Inheritance Pattern of:
Wiskott-Aldrich syndrome
A
Inheritance Pattern
Wiskott-Aldrich syndrome - X-linked Recessive
Mneumonic: Obliviously Female Will Often Give Her Boys Her x-Linked Disorders
3
Q
Genetics - First Aid 2019
Genetic terms: Example(s) for -
Loss of heterozygosity
A
Genetics - First Aid 2019
Example(s) for - Loss of heterozygosity
Retinoblastoma and the “two-hit hypothesis,”
Lynch syndrome (HNPCC), Li-Fraumeni
syndrome.
4
Q
Genetic disorders by Chromosome
Cri-du-chat syndrome, familial adenomatous polyposis
A
Genetic disorders by Chromosome
Cri-du-chat syndrome, familial adenomatous polyposis
Chromosome 5
5
Q
Inheritance Pattern of:
Familial Adenomatous Polyposis
A
Inheritance Pattern
Familial Adenomatous Polyposis- Autosomal Dominant
6
Q
Inheritance Pattern of:
Ornithine transcarbamylase deficiency
A
Inheritance Pattern
Ornithine transcarbamylase deficiency - X-linked Recessive
Mneumonic: Obliviously Female Will Often Give Her Boys Her x-Linked Disorders
7
Q
Genetics - First Aid 2019
Genetic terms: Example(s) for -
Codominance
A
Genetics - First Aid 2019
Example(s) for - Codominance
Blood groups A, B, AB; α1-antitrypsin
deficiency; HLA groups.
8
Q
Inheritance Pattern of:
Friedreich ataxia
A
Inheritance Pattern
Friedreich ataxia - Autosomal Recessive
9
Q
Inheritance Pattern of:
Achondroplasia
A
Inheritance Pattern
Achondroplasia - Autosomal Dominant
10
Q
Inheritance Pattern of:
Bruton agammaglobulinemia
A
Inheritance Pattern
Bruton agammaglobulinemia - X-linked Recessive
Mneumonic: Obliviously Female Will Often Give Her Boys Her x-Linked Disorders
11
Q
Genetic disorders by Chromosome
von Hippel-Lindau disease, renal cell carcinoma
A
Genetic disorders by Chromosome
von Hippel-Lindau disease, renal cell carcinoma
Chromosome 3
12
Q
Inheritance Pattern of:
Ocular albinism
A
Inheritance Pattern
Ocular albinism - X-linked Recessive
Mneumonic: Obliviously Female Will Often Give Her Boys Her x-Linked Disorders
13
Q
Modes of inheritance
Autosomal dominant: Often due to defects in ________ genes. Many generations, both males and females are affected.
A
Modes of inheritance
Autosomal dominant: Often due to defects in structural genes. Many generations, both males and females are affected.
14
Q
Modes of inheritance
What mode of Inheritance is presented here?
A
Modes of inheritance
Autosomal ressecive
15
Q
Inheritance Pattern of:
Li-Fraumeni syndrome
A
Inheritance Pattern
Li-Fraumeni syndrome - Autosomal Dominant
16
Q
Genetics - First Aid 2019
Genetic terms: Definition
Locus heterogeneity
A
Genetics - First Aid 2019
Definition: Locus heterogeneity
Mutations at different loci can produce a similar
phenotype.
17
Q
Inheritance Pattern of:
Oculocutaneous albinism
A
Inheritance Pattern
Oculocutaneous albinism- Autosomal Recessive
18
Q
Inheritance Pattern of:
von Hippel-Lindau disease
A
Inheritance Pattern
von Hippel-Lindau disease - Autosomal Dominant
19
Q
Genetics - First Aid 2019
Genetic terms: Definition
Pleiotropy
A
Genetics - First Aid 2019
Definition: Pleiotropy
One gene contributes to multiple phenotypic
effects.
20
Q
Inheritance Pattern of:
Fabry disease
A
Inheritance Pattern
Fabry disease- X-linked Recessive
Mneumonic: Obliviously Female Will Often Give Her Boys Her x-Linked Disorders
21
Q
Inheritance Pattern of:
Multiple Endocrine Neoplasias (MEN)
A
Inheritance Pattern
Multiple Endocrine Neoplasias (MEN) - Autosomal Dominant
22
Q
Genetic disorders by Chromosome
ADPKD (PKD1), α-globin gene defects (eg, α-thalassemia), tuberous sclerosis (TSC2)
A
Genetic disorders by Chromosome
ADPKD (PKD1), α-globin gene defects (eg, α-thalassemia), tuberous sclerosis (TSC2)
Chromosome 16
23
Q
Inheritance Pattern of:
Mucopolysaccharidoses (except Hunter syndrome)
A
Inheritance Pattern
Mucopolysaccharidoses - Autosomal Recessive
(except Hunter syndrome)
24
Q
Genetics - First Aid 2019
Genetic terms: Example(s) for -
Variable expressivity
A
Genetics - First Aid 2019
Example(s) for - Variable expressivity
2 patients with neurofibromatosis type 1 (NF1) or Polydactyly may have varying disease severity.
25
**_Genetic disorders by Chromosome_**
Neurofibromatosis type 1, BRCA1, TP53
**_Genetic disorders by Chromosome_**
Neurofibromatosis type 1, BRCA1, TP53
**Chromosome 17**
26
**_Modes of inheritance_**
**_Mitochondrial inheritance:_** Mitochondrial myopathies
**_Modes of inheritance_**
**_Mitochondrial myopathies_** - rare disorders;
often present with myopathy, lactic acidosis,
and CNS disease, eg, **MELAS syndrome**
(mitochondrial encephalomyopathy, lactic
acidosis, and stroke-like episodes). 2° to
failure in oxidative phosphorylation.
27
**_Inheritance Pattern of:_**
Hereditary Spherocytosis
**_Inheritance Pattern_**
Hereditary Spherocytosis - Autosomal Dominant
28
**_Disorders of imprinting_**
_Prader-Willi syndrome - Chromosome and Disomy Associated:_
**_Disorders of imprinting_**
_Prader-Willi syndrome - Associated with:_
Associated with a mutation or deletion of chromosome **_15_** of paternal origin. **P**rader has no **P**apa (Paternal deletion).
25% of cases are due to **_maternal uniparental disomy_**.
29
**_Inheritance Pattern of:_**
hereditary hemorrhagic telangiectasia (Osler-Weber-Rendu syndrome)
**_Inheritance Pattern_**
hereditary hemorrhagic telangiectasia (Osler-Weber-Rendu syndrome) - Autosomal Dominant
30
**_Inheritance Pattern of:_**
Hemochromatosis
**_Inheritance Pattern_**
Hemochromatosis - Autosomal Recessive
31
**_Genetics - First Aid 2019_**
Genetic terms: Example(s) for -
Heteroplasmy
**_Genetics - First Aid 2019_**
_Example(s) for - Heteroplasmy_
mtDNA passed from mother to all children.
32
**_Genetics - First Aid 2019_**
Genetic terms: Definition
Anticipation
**_Genetics - First Aid 2019_**
_Definition: Anticipation_
Increased severity or earlier onset of disease in
succeeding generations.
33
**_Genetics - First Aid 2019_**
If a population is in _**Hardy-Weinberg
equilibrium**_ and if p and q are the frequencies
of separate alleles, then: p2 + 2pq + q2 = 1 and
p + q = 1, which implies that:
**_Genetics - First Aid 2019_**
**_Hardy-Weinberg equilibrium: The values of p and q remain constant from generation to generation._**
p2 = frequency of homozygosity for allele A
q2 = frequency of homozygosity for allele a
2pq = frequency of heterozygosity (carrier
frequency, if an autosomal recessive disease).
The frequency of an X-linked recessive disease
in males = q and in females = q2.
34
**_Genetics - First Aid 2019_**
Genetic terms: Example(s) for -
Incomplete Penetrance
**_Genetics - First Aid 2019_**
_Example(s) for - Incomplete Penetrance_
BRCA1 gene mutations do not always result in
breast or ovarian cancer.
35
**_Inheritance Pattern of:_**
Cystic Fibrosis
**_Inheritance Pattern_**
Cystic Fibrosis - Autosomal Recessive
36
**_Inheritance Pattern of:_**
Marfan syndrome
**_Inheritance Pattern_**
Marfan syndrome - Autosomal Dominant
37
**_Genetics - First Aid 2019_**
Genetic terms: Definition
Incomplete Penetrance
**_Genetics - First Aid 2019_**
_Definition: Incomplete Penetrance_
Not all individuals with a mutant genotype
show the mutant phenotype.
% penetrance × probability of inheriting
genotype = risk of expressing phenotype.
38
**_Inheritance Pattern of:_**
PKU
**_Inheritance Pattern_**
Phenylketonuria - Autosomal Recessive
39
**_Genetics - First Aid 2019_**
Genetic terms: Definition
Dominant negative mutation
**_Genetics - First Aid 2019_**
_Definition: Dominant negative mutation_
Exerts a dominant effect. A heterozygote
produces a nonfunctional altered protein that
also prevents the normal gene product from
functioning.
40
**_Genetics - First Aid 2019_**
Genetic terms: Definition
Allelic heterogeneity
**_Genetics - First Aid 2019_**
_Definition: Allelic heterogeneity_
Different mutations in the same locus
produce the same phenotype.
41
**_Genetic disorders by Chromosome_**
Hemochromatosis (HFE)
**_Genetic disorders by Chromosome_**
Hemochromatosis (HFE)
**Chromosome 6**
42
**_Genetics - First Aid 2019_**
Genetic terms: Definition
X-inactivation (lyonization)
**_Genetics - First Aid 2019_**
_Definition: X-inactivation (lyonization)_
one copy of female X chromosome forms a
transcriptionally inactive Barr body. Female
carriers variably affected depending on the
pattern of inactivation of the X chromosome
carrying the mutant vs normal gene.
43
**_Genetics - First Aid 2019_**
Genetic terms: Definition
Linkage disequilibrium
**_Genetics - First Aid 2019_**
_Definition: Linkage disequilibrium_
Tendency for certain alleles at 2 linked
loci to occur together more or less often
than expected by chance. Measured in a
population, not in a family, and often varies in
different populations.
44
**_Genetics - First Aid 2019_**
Genetic terms: Example(s) for -
Pleiotropy
**_Genetics - First Aid 2019_**
_Example(s) for - Pleiotropy_
```
Untreated phenylketonuria (PKU) manifests with
light skin, intellectual disability, and musty body
odor.
```
45
**_Inheritance Pattern of:_**
Wilson disease
**_Inheritance Pattern_**
Wilson disease - Autosomal Recessive
46
**_Modes of inheritance_**
What mode of Inheritance is presented here?
**_Modes of inheritance_**
## Footnote
**Autosomal dominant**
47
**_Genetics - First Aid 2019_**
Genetic terms: Example(s) for -
Mosaicism
**_Genetics - First Aid 2019_**
_Example(s) for - Mosaicism_
**_McCune-Albright syndrome_**—Gs-protein
activating mutation leads to unilateral
café-au-lait spots with ragged edges, polyostotic fibrous dysplasia (bone is replaced by collagen and fibroblasts), and at least one endocrinopathy (eg, precocious puberty). Lethal if mutation occurs before fertilization (affecting all cells), but survivable in patients with mosaicism.
48
**_Inheritance Pattern of:_**
Thalassemias
**_Inheritance Pattern_**
Thalassemias - Autosomal Recessive
49
**_Genetics - First Aid 2019_**
Genetic terms: Definition
Uniparental disomy
**_Genetics - First Aid 2019_**
_Definition: Uniparental disomy_
Offspring receives 2 copies of a chromosome from
1 parent and no copies from the other parent. Uniparental is euploid. Most occurrences of uniparental disomy result in normal phenotype.
50
**_Modes of inheritance_**
**_Autosomal dominant:_** Often _______ (multiple apparently unrelated effects) and _______ \_\_\_\_\_\_\_ (different between individuals). Family history crucial
to diagnosis. With one affected (heterozygous)
parent, on average, ½ of children affected.
**_Modes of inheritance_**
**_Autosomal dominant:_** Often **pleiotropic** (multiple apparently unrelated effects) and **variably expressive** (different between individuals). Family history crucial
to diagnosis. With one affected (heterozygous)
parent, on average, ½ of children affected.
51
**_Disorders of imprinting_**
_AngelMan syndrome - Chromosome and Disomy Associated:_
**_Disorders of imprinting_**
_AngelMan syndrome - Associated with:_
Associated with mutation or deletion of
the **UBE3A gene on the maternal copy** of
chromosome 15.
5% of cases due to **paternal uniparental disomy**.
52
**_Inheritance Pattern of:_**
ARPKD
**_Inheritance Pattern_**
ARPKD - Autosomal Recessive
(Autosomal Recessive Polycystic Kidney Disease)
53
**_Modes of inheritance_**
**_Mitochondrial inheritance:_** Transmitted only through the mother. ___ offspring of affected females may show signs of disease. _______ \_\_\_\_\_\_\_\_ in a population or even within a family due to heteroplasmy.
**_Modes of inheritance_**
**_Mitochondrial inheritance:_** Transmitted only through the mother. **All** offspring of affected females may show signs of disease. **Variable expression** in a population or even
within a family due to heteroplasmy.
54
**_Inheritance Pattern of:_**
Tuberous Sclerosis
**_Inheritance Pattern_**
Tuberous Sclerosis - Autosomal Dominant
55
**_Inheritance Pattern of:_**
Hunter syndrome
**_Inheritance Pattern_**
**H**unter syndrome - X-linked Recessive
Mneumonic: **O**bliviously **F**emale **W**ill **O**ften **G**ive **H**er **B**oys **H**er x-**L**inked **D**isorders
56
**_Genetics - First Aid 2019_**
Genetic terms: Definition
Codominance
**_Genetics - First Aid 2019_**
_Definition: Codominance_
Both alleles contribute to the phenotype of the
heterozygote.
57
**_Genetics - First Aid 2019_**
Genetic terms: Example(s) for -
Anticipation
**_Genetics - First Aid 2019_**
_Example(s) for - Anticipation_
Trinucleotide repeat diseases (eg, Huntington
disease).
58
**_Genetics - First Aid 2019_**
Genetic terms: Definition
Loss of heterozygosity
**_Genetics - First Aid 2019_**
_Definition: Loss of Heterozygosity_
If a patient inherits or develops a mutation in
a tumor suppressor gene, the complementary
allele must be deleted/mutated before cancer
develops. This is not true of oncogenes.
59
**_Genetic disorders by Chromosome_**
ADPKD (PKD2), achondroplasia, Huntington disease
**_Genetic disorders by Chromosome_**
ADPKD (PKD2), achondroplasia, Huntington disease
**Chromosome 4**
60
**_Genetics - First Aid 2019_**
Genetic terms: Definition
Imprinting
**_Genetics - First Aid 2019_**
_Imprinting_
one gene copy is silenced by methylation, and only the other copy is expressed → parent-of-origin effects.
61
**_Inheritance Pattern of:_**
Sickle Cell anemia
**_Inheritance Pattern_**
Sickle Cell anemia - Autosomal Recessive
62
**_Genetic disorders by Chromosome_**
Edwards syndrome
**_Genetic disorders by Chromosome_**
Edwards syndrome
**Chromosome 18**
63
**_Genetic disorders by Chromosome_**
Prader-Willi syndrome, Angelman syndrome, Marfan syndrome
**_Genetic disorders by Chromosome_**
Prader-Willi syndrome, Angelman syndrome, Marfan syndrome
**Chromosome 15**
64
**_Genetics - First Aid 2019_**
Genetic terms:
Hardy-Weinberg law assumptions (4)
**_Genetics - First Aid 2019_**
_Hardy-Weinberg law assumptions include:_
* No mutation occurring at the locus
* Natural selection is not occurring
* Completely random mating
* No net migration
65
**_Genetics - First Aid 2019_**
Genetic terms: Definition
Somatic Mosaicism
**_Genetics - First Aid 2019_**
_Definition: Somatic Mosaicism_
Presence of genetically distinct cell lines in the
same individual. In Somatic mosaicism, the mutation arises from mitotic errors after fertilization and propagates through multiple tissues or organs.
66
**_Genetic disorders by Chromosome_**
Down syndrome
**_Genetic disorders by Chromosome_**
Down syndrome
**Chromosome 21**
67
**_Modes of inheritance_**
**_X-linked Dominant:_** Example(s)
**_Modes of inheritance_**
**_Hypophosphatemic rickets_**—formerly known as
vitamin D–resistant rickets. Inherited disorder
resulting in higher phosphate wasting at proximal
tubule. Results in rickets-like presentation.
Other examples: **fragile X syndrome**, **Alport
syndrome.**
68
**_Genetic disorders by Chromosome_**
Wilms tumor, β-globin gene defects (eg, sickle cell disease, β-thalassemia), MEN1
**_Genetic disorders by Chromosome_**
Wilms tumor, β-globin gene defects (eg, sickle cell disease, β-thalassemia), MEN1
**Chromosome 11**
69
**_Inheritance Pattern of:_**
Duchenne (and Becker) muscular dystrophy
**_Inheritance Pattern_**
**D**uchenne (and Becker) muscular dystrophy - X-linked Recessive
Mneumonic: **O**bliviously **F**emale **W**ill **O**ften **G**ive **H**er **B**oys **H**er x-**L**inked **D**isorders
70
**_Inheritance Pattern of:_**
Hemophilia A and B
**_Inheritance Pattern_**
**H**emophilia A and B - X-linked Recessive
Mneumonic: **O**bliviously **F**emale **W**ill **O**ften **G**ive **H**er **B**oys **H**er x-**L**inked **D**isorders
71
**_Modes of inheritance_**
* *_X-linked recessive:_** Sons of heterozygous mothers have a ___ chance of being affected. No \_\_\_\_-to-\_\_\_\_
transmission. Skips generations.
**_Modes of inheritance_**
* *_X-linked recessive:_** Sons of heterozygous mothers have a **50%** chance of being affected. No **male-to-male**
transmission. Skips generations.
72
**_Inheritance Pattern of:_**
Huntington disease
**_Inheritance Pattern_**
Huntington disease - Autosomal Dominant
73
**_Modes of inheritance_**
**_X-linked recessive:_** Commonly more severe in males. Females usually must be _________ to be affected.
**_Modes of inheritance_**
**_X-linked recessive:_** Commonly more severe in males. Females usually must be **homozygous** to be affected.
74
**_Genetics - First Aid 2019_**
Genetic terms: Example(s) for -
Uniparental disomy
**_Genetics - First Aid 2019_**
_Example(s) for - Uniparental disomy_
Consider UPD in an individual manifesting a _recessive_
disorder when only one parent is a carrier.
Examples: _Prader-Willi and Angelman
syndromes._
75
**_Disorders of imprinting_**
_AngelMan syndrome - Signs and Symptoms_
**_Disorders of imprinting_**
_AngelMan syndrome:_ Results in inappropriate laughter (“happy puppet”), seizures, ataxia, and severe intellectual
disability.
76
**_Disorders of imprinting_**
_Prader-Willi syndrome:Signs and Symptoms_
**_Disorders of imprinting_**
_Prader-Willi syndrome:_ Results
in hyperphagia, obesity, intellectual disability,
hypogonadism, and hypotonia.
77
**_Genetics - First Aid 2019_**
Genetic terms: Example(s) for -
Dominant negative mutation
**_Genetics - First Aid 2019_**
_Example(s) for - Dominant negative mutation_
Mutation of a transcription factor in its allosteric
site. Nonfunctioning mutant can still bind
DNA, preventing wild-type transcription factor
from binding.
78
**_Genetic disorders by Chromosome_**
Neurofibromatosis type 2, DiGeorge syndrome
**_Genetic disorders by Chromosome_**
Neurofibromatosis type 2, DiGeorge syndrome (22q11)
**Chromosome 22**
79
**_Inheritance Pattern of:_**
Neurofibromatosis type 1 (von
Recklinghausen disease) and type 2
**_Inheritance Pattern_**
Neurofibromatosis type 1 (von
Recklinghausen disease) and type 2 - Autosomal Dominant
80
**_Modes of inheritance_**
**_Autosomal recessive:_** Higher risk in __________ families. Unaffected individual with affected sibling has
2/3 probability of being a carrier.
**_Modes of inheritance_**
**_Autosomal recessive:_** Higher risk in **consanguineous** families. Unaffected individual with affected sibling has
2/3 probability of being a carrier.
81
**_Disorders of imprinting_**
_AngelMan syndrome: Silent Gene_
**_Disorders of imprinting_**
_Angel**M**an syndrome: Silent Gene_ Paternally derived gene is silenced (imprinted). Disease occurs when the **M**aternal allele is deleted or mutated.
82
**_Genetics - First Aid 2019_**
Genetic terms: Definition
Uniparental disomy - Heterodisomy Vs. IsodIsomy
**_Genetics - First Aid 2019_**
_Definition: Heterodisomy Vs. Isodisomy_
Heterod**I**somy (heterozygous) indicates a meiosis **I** error. **I**sod**I**somy (homozygous) indicates a meiosis **II** error or postzygotic chromosomal duplication of one of a pair of chromosomes, and loss of the other of the original pair.
83
**_Modes of inheritance_**
**_Autosomal recessive:_** With 2 carrier (heterozygous) parents, on average: _ of children will be affected (homozygous), _ of children will be carriers, and _ of
children will be neither affected nor carriers.
**_Modes of inheritance_**
**_Autosomal recessive:_** With 2 carrier (heterozygous) parents, on average: **_¼_** of children will be affected (homozygous), **_½_** of children will be carriers, and **_¼_** of
children will be neither affected nor carriers.
84
**_Modes of inheritance_**
What mode of Inheritance is presented here?
\*Hint: Fathers transmit to all daughters
**_Modes of inheritance_**
## Footnote
**X-linked dominant**
85
**_Modes of inheritance_**
What mode of Inheritance is presented here?
\*Hint: All offspring of affected females may show signs of
disease.
**_Modes of inheritance_**
## Footnote
**Mitochondrial Inheritance**
86
**_Inheritance Pattern of:_**
Lesch-Nyhan syndrome
**_Inheritance Pattern_**
**L**esch-Nyhan syndrome - X-linked Recessive
Mneumonic: **O**bliviously **F**emale **W**ill **O**ften **G**ive **H**er **B**oys **H**er x-**L**inked **D**isorders
87
**_Modes of inheritance_**
**_X-linked Dominant:_** Transmitted through both parents. Mothers transmit to 50% of daughters and sons; fathers
transmit to ___ daughters but no sons.
**_Modes of inheritance_**
**_X-linked Dominant:_** Transmitted through both parents. Mothers transmit to 50% of daughters and sons; fathers
transmit to **_all_** daughters but no sons.
88
**_Genetics - First Aid 2019_**
Genetic terms: Definition
Heteroplasmy
**_Genetics - First Aid 2019_**
_Definition: Heteroplasmy_
Presence of both normal and mutated
mtDNA, resulting in variable expression in
mitochondrially inherited disease.
89
**_Genetics - First Aid 2019_**
Genetic terms: Definition
Gonadal Mosaicism
**_Genetics - First Aid 2019_**
_Definition: Gonadal Mosaicism_
Presence of genetically distinct cell lines in the
same individual. In Gonadal mosaicism, the mutation is only in egg or sperm cells. If parents and relatives do not
have the disease, suspect gonadal (or germline) mosaicism.
90
**_Genetic disorders by Chromosome_**
Fragile X syndrome, X-linked agammaglobulinemia, Klinefelter syndrome (XXY)
**_Genetic disorders by Chromosome_**
## Footnote
**Chromosome X**
91
**_Inheritance Pattern of:_**
Glycogen storage diseases
**_Inheritance Pattern_**
Glycogen storage diseases - Autosomal Recessive
92
**_Modes of inheritance_**
**_Mitochondrial inheritance:_** Leber hereditary optic neuropathy
**_Modes of inheritance_**
**_Leber hereditary optic neuropathy_** - cell
death in optic nerve neurons → subacute
bilateral vision loss in teens/young adults, 90%
males. Usually permanent.
93
**_Inheritance Pattern of:_**
Familial Hypercholesterolemia
**_Inheritance Pattern_**
Familial Hypercholesterolemia - Autosomal Dominant
94
**_Inheritance Pattern of:_**
G6PD deficiency
**_Inheritance Pattern_**
**G**6PD deficiency - X-linked Recessive
Mneumonic: **O**bliviously **F**emale **W**ill **O**ften **G**ive **H**er **B**oys **H**er x-**L**inked **D**isorders
95
**_Genetics - First Aid 2019_**
Genetic terms: Definition
Variable expressivity
**_Genetics - First Aid 2019_**
_Definition: Variable expressivity_
Patients with the same genotype have varying
phenotypes.
96
**_Genetics - First Aid 2019_**
Genetic terms: Example(s) for -
Locus heterogeneity
**_Genetics - First Aid 2019_**
_Example(s) for - Locus heterogeneity_
Albinism.
97
**_Genetic disorders by Chromosome_**
Friedreich ataxia, tuberous sclerosis (TSC1)
**_Genetic disorders by Chromosome_**
Friedreich ataxia, tuberous sclerosis (TSC1)
**Chromosome 9**
98
**_Disorders of imprinting_**
_Prader-Willi syndrome:Silent Gene_
**_Disorders of imprinting_**
_**P**rader-Willi syndrome:Silent Gene_ Maternally derived genes are silenced (imprinted). Disease occurs when the **P**aternal allele is deleted or mutated.
99
**_Inheritance Pattern of:_**
Kartagener syndrome
**_Inheritance Pattern_**
Kartagener syndrome - Autosomal Recessive
100
**_Genetic disorders by Chromosome_**
Patau syndrome, Wilson disease, retinoblastoma (RB1), BRCA2
**_Genetic disorders by Chromosome_**
Patau syndrome, Wilson disease, retinoblastoma (RB1), BRCA2
**Chromosome 13**
101
**_Genetic disorders by Chromosome_**
Williams syndrome, Cystic fibrosis
**_Genetic disorders by Chromosome_**
Williams syndrome, Cystic fibrosis
**Chromosome 7**
102
**_Inheritance Pattern of:_**
Myotonic Muscular Dystrophy
**_Inheritance Pattern_**
Myotonic Muscular Dystrophy - Autosomal Dominant
103
**_Genetics - First Aid 2019_**
Genetic terms: Example(s) for -
Allelic heterogeneity
**_Genetics - First Aid 2019_**
_Example(s) for - Allelic heterogeneity_
β-thalassemia.
104
**_Modes of inheritance_**
**_Autosomal recessive:_** Often due to ______ deficiencies. Usually seen in only 1 generation. Commonly more severe than dominant disorders; patients often present
in childhood.
**_Modes of inheritance_**
**_Autosomal recessive:_** Often due to **enzyme** deficiencies. Usually seen in only 1 generation. Commonly more severe than dominant disorders; patients often present
in childhood.
105
**_Inheritance Pattern of:_**
Sphingolipidoses
**_Inheritance Pattern_**
Sphingolipidoses - Autosomal Recessive
(except Fabry disease)
106
**_Inheritance Pattern of:_**
ADPKD
**_Inheritance Pattern_**
ADPKD - Autosomal Dominant
(Autosomal Dominant Polycystic Kidney Disease)
