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Disease MCB Flashcards

1
Q

Acanthocytosis/ Spur Cell Anemia

Location, Defect and Mode of inheritance

A

Location: Cell Membrane

Defect: RBC cell membrane

Mode of Inheritance: Acquired

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2
Q

Acanthocytosis/ Spur Cell Anemia Mechanism

A

Haemolytic anemia caused by excess cholesterol transferred to outer leaflet creates flat, scalloped cells with projections (spur cells), which increase SA of outer bilayer making cells less deformable; sequestration and destruction by spleen;
associated with chronic liver disease (i.e. alcohol liver disease)

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3
Q

Acanthocytosis/ Spur Cell Anemia Characteristics

A

Characteristics: Ascites, jaundiced, caput medusa

Key Words: acanthocytes, cholesterol, chronic liver disease

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4
Q

Hereditary Spherocytosis

Location, Defect, and Mode of Inheritance

A

Location: Cell Membrane
Defect: RBC cytoskeletal membrane defect due to nonfunctional skeletal membrane protein; spectrin*, ankyrin, or protein 4.1

MOI: Autosomal Dominant

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5
Q

Hereditary Spherocytosis Mechanism

A

Haemolytic anemia caused by spectrin deficiency causing unstable membrane – loses membrane fragments and becomes less deformable resulting in sequestration and destruction by spleen

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6
Q

Hereditary Spherocytosis Characteristic

A

Characteristics: Splenomegaly, jaundice, gallstones

Key Words: spectrin, ankyrin, protein 4.1

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7
Q

Emery-Dreifuss Muscular Dystrophy Location, Defect, and MOI

A

Location: Nucleus
Defect: Mutated Emerin or Lamin A/C defected nuclear envelope

Mode of Inheritance: X-linked if Emerin;
Autosomal dominant in Lamin A/C

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8
Q

Emery-Dreifuss Muscular Dystrophy Mechanism

A

Defect in lamin assembly/attachment to nuclear envelope causes fragile nuclear envelope resulting in disruption of nuclear function: aberrant distribution of chromosomes is altered

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9
Q

Emery-Dreifuss Muscular Dystrophy Characteristics

A

Characteristics: Contractures (especially in elbows, ankles, neck), muscle
weakness and atrophy, heart conduction defects and arrhythmias, sudden heart failure

Key Words: emerin, contracture, sudden heart failure

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10
Q

Dilated Cardiomyopathy Location, Defect, and MOI

A

Location: Nucleus

Defect: Lamin A/C defect (RARE CAUSE)

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11
Q

Dilated Cardiomyopathy Mechanism

A

Defected lamin causes fragile nuclear lamina and subsequent cell death

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12
Q

Dilated Cardiomyopathy Characteristics

A

Characteristics: CHF

Key Words: lamin A/C,

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13
Q

Lipodystrophy Location, Defect, and MOI

A

Location: Nucleus

Defect: Lamin A/C defect

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14
Q

Lipodystrophy Mechanism

A

preLamin A interacts with adipocyte TF (impaired adipocyte differentiation)

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15
Q

Lipodystrophy Characteristics

A

Characteristics: accumulation of adipose tissue in face and neck, peripheral lipoatrophy with muscle prominence

Key Words: lamin A/C, preLamin A, adipocute accumulation, muscle prominence

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16
Q

Hutchinson-Gilford Progeria Syndrome Location, Defect, MOI

A

Location: Nucleus

efect: Lamin A defect

MOI: Autosomal dominant (sporadic)

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17
Q

Hutchinson-Gilford Progeria Syndrome Mechanism

A

Defect in lamin causes fragile nuclear envelope (bleb formation, loss of peripheral heterochromatin, NPC clustering) resulting in progressive nuclear damage and premature cell death

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18
Q

Hutchinson-Gilford Progeria Syndrome Characteristics

A

Characteristics: normal at birth/early infancy but failure to thrive around 18-24 mos, prominent eyes, alopecia, loss of subcutaneous fat, joint stiffness, arteriosclerosis ~5 y/o, 80% die from MI or CHF

Key Words: bleb formation, premature cell death, alopecia, prominent eyes,arteriosclerosis

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19
Q

Spinal Muscular Atrophy (Type I,II,III) – infantile, intermediate, adult Location, Defect, MOI

A

Location: Nucleus

Defect: Mutation of SMN protein in gem of nucleus

Mode of Inheritance: Recessive

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20
Q

Spinal Muscular Atrophy (Type I,II,III – infantile, intermediate, adult Mechanism

A

Mutated SMN causes defective snRNP assembly subsequent defective pre-mRNA splicing causing loss of motor neurons

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21
Q

Spinal Muscular Atrophy (Type I,II,III – infantile, intermediate, adult Characteristics

A

Characteristics: sudden onset, rapid progression; muscle weakness and atrophy, hypotonia, dysphagia and feeding difficulties, RTIs

Key Words: SMN in Gems, defected snRNP assembly, hypotonia, *most common genetically related neonatal death

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22
Q

Cystic Fibrosis Location, Defect, MOI

A

Location: RER and Golgi

Defect: Protein folding defect defective transport from rER to Golgi; mutation in CFTR (Cl- ion channel) – single AA deletion of F508

Mode of Inheritance: Autosomal recessive

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23
Q

Cystic Fibrosis Mechanism

A

CFTR is misfolded in the ER so it keeps getting ejected back to cytosol and degraded in proteasomes

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24
Q

Cystic Fibrosis Characteristics

A

Characteristics: young white kid; normal at birth, failure to thrive, recurrent pneumonia, sputum +pseudomonas; PE: scattered rales/crackles throughout lungs, rhonchi; diagnostic: axillary sweat test; bronchiectasis; respiratory
failure is most common cause of death (clubbing is often seen due to respiratory insufficiency but this is not characteristic of just CF – seen in other diseases as well)

Key Words: CFTR mutation, fibrosis in lungs, sweat, autosomal recessive, respiratory failure

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25
Familial Hypercholesterolemia L,D,MOI
Location: RER and Golgi Defect: Protein folding defect defective transport from rER to Golgi; mutation of LDL-R (cell surface receptor for LDL; transmembrane protein) – CLASS II Mode of Inheritance: Genetically related
26
Familial Hypercholesterolemia Mechanism
Mutation inhibits proper folding of LDL-R  ejected from ER, polyubiquinated, degraded by proteasome
27
Familial Hypercholesterolemia
Characteristics: increased plasma cholesterol levels; increased LDL synthesis; major risk factor for CHD, premature atherosclerosis, Xanthomata, corneal arcus, Xanthelasmata Key Words: LDL-R, CHD (CAD), plasma cholesterol, Xanthomata, Xanthelasmata
28
I Cell Disease L,D,MOI
Location: RER and Golig Defect: Transport defect – absence M6P protein tag (N-acetylglucosamine phosphotransferase deficiency in cis-golgi) – also considered a LYSOSOMAL STORAGE
29
I Cell Disease mechanism
The absence of M6P tag results in lysosomal enzymes (aka acid hydrolases) being sent to PM and secreted extracellularly (default pathway), rather than being sent to lysosomes. Degradation of cellular inclusions within the lysosome does not take place because the lysosomes are devoid of lysosomal enzymes  accumulation of inclusions. [*Note: the defect is NOT in the lysosomal enzymes, but rather in the Golgi-resident modification enzyme mentioned above
30
I Cell Disease Characteristics
Characteristics: progressive disease; high levels of acid hydrolases in the blood; skeletal abnormalities, coarse facial features, restricted joint movement, psychomotor retardation, enlarged spleen, liver, & heart valves, death due to CHF or RTI, life expectancy ~10 years Key Words: absence of M6P, waste products in inclusion bodies, coarse facial features, enlarged liver/spleen, death CHF
31
Botulism L,D,MOI
Location: Exocytosis and Endocytosis Defect: Inhibits SNARE/exocytosis Mode of Inheritance: Acquired from Clostridium botulinum toxin (foodborne, wound, infants eating off floor)
32
Botulism Mechanism
Mechanism: Cleaves synaptobrevin (V SNARE) of vesicles carrying ACh (stimulatory NT) unable to interact with syntaxin inhibits exocytosis/release of NT at NMJ
33
Botulism Characteristics
Characteristics: Paralysis of respiratory and skeletal muscles (potentially fatal) because stimulatory NT is not released to elicit muscle contraction flaccid paralysis; “floppy baby syndrome” – hypotonia, hyporeflexia Key Words: flaccid paralysis, synaptobrevin cleaved, ACh-stimulatory
34
Tetanus L,D,MOI
Defect: Inhibits SNARE/exocytosis Mode of Inheritance: Acquired from Clostridium tetani (wound contamination
35
Tetanus Mechanism
Cleaves synaptobrevin of vesicles carrying GABA & glycine (inhibitory NTs) unable to interact with syntaxin inhibits exocytosis/release of NT
36
Tetanus Characteristics
Characteristics: Prolonged contraction of skeletal muscles (potentially fatal)  violent spastic paralysis; 1st sign – trismus (lock jaw), neck stiffness, dysphagia, pectoral & calf muscle rigity, muscle rigity & spasms; spatula test Key Words: spastic paralysis, synaptobrevin cleaved, GABA&glycine-inhibitory, trismus, spatula test
37
Familial Hypercholesterolemia Defect and MOI
Defect: Endocytosis Mode of Inheritance: Autosomal dominant
38
Familial Hypercholesterolemia Mechanism
Mechanism: LDL-R does not cluster in the membrane so endocytosis is not effective CLASS IV
39
Familial Hypercholesterolemia Characteristics
Characteristics: increased plasma cholesterol levels; increased LDL synthesis; major risk factor for CHD, premature atherosclerosis, Xanthomata, corneal arcus, Xanthelasmata Key Words: LDL-R, CHD (CAD), plasma cholesterol, Xanthomata, Xanthelasmata
40
I Cell Disease (MUCOLIPIDOSIS II) L, D, MOI
Location: Lysosomes Defect: Lysosomal storage disease – absence M6P protein tag (due to defected N- acetylglucosamine phosphotransferase in cis golgi) Mode of Inheritance: Autosomal recessive
41
I Cell Disease (MUCOLIPIDOSIS II) Mechanism
The absence of M6P tag results in almost all hydrolytic enzymes secreted extracellularly, rather than being sent to lysosomes to function in degradation undigested substrates (glycolipids/glycoproteins/GAGs) accumulate in inclusion bodies
42
I Cell Disease (MUCOLIPIDOSIS II) Characteristics
Characteristics: progressive disease; high levels of acid hydrolases in the blood; skeletal abnormalities, coarse facial features, restricted joint movement, psychomotor retardation, enlarged spleen, liver, & heart valves, death due to CHF or RTI, life expectancy ~10 years Key Words: absence of M6P, lysosomal storage disease, waste products in inclusion bodies, coarse facial features, enlarged liver/spleen, death CHF
43
Pseudo-Hurler Polydystrophy (MUCOLIPIDOSIS III) | L,D,MOI
Location: Lysosomes Defect: Lysosomal storage disease - partial dysfunction of N-acetylglucosamine phosphotransferase in cis golgi Mode of Inheritance: Autosomal recessive MOD: Auto recessive
44
Pseudo-Hurler Polydystrophy (MUCOLIPIDOSIS III) Mechanism
Mild form of I Cell Disease in which pt has partial function of Nacetylglucosamine phosphotransferase some enzymes are tagged with M6P and get to lysosomes but not enough
45
Pseudo-Hurler Polydystrophy (MUCOLIPIDOSIS III) Characteristics
Characteristics: later onset than I Cell, survival into adulthood
46
Hurler Syndrome (MPS IH) L,D,MOI
Lysosomal storage disease - deficiency in alpha-L-iduronidase Mode of Inheritance: Autosomal recessive
47
Hurler Syndrome (MPS IH) Mechanism
Deficient alpha-L-iduronidase  accumulation of 2 types of GAGs: dermatan sulphate & heparan sulphate
48
Hurler Syndrome (MPS IH) Characteristics
Characteristics: progressive; physical & mental deterioration, hepatosplenomegaly, skeletal deformity, coarse facial features, hirsutism, corneal clouding; death before 10 Key Words: alpha-L-iduronidase, dermatan sulphate & heparan sulphate, hepatosplenomegaly, coarse facial features, skeletal deformity, hirsutism, corneal clouding
49
Scheie & Hurler-Scheie Syndrome (MPS IS & MPS HIS) L, D, MOI
Location: Lysosomes Defect: Lysosomal storage disease - Residual alpha-L-iduronidase Mode of Inheritance: Autosomal recessive
50
Scheie & Hurler-Scheie Syndrome (MPS IS & MPS HIS) Mechanism
Mechanism: Mild form of Hurler Syndrome so partial breakdown of GAGs
51
Scheie & Hurler-Scheie Syndrome (MPS IS & MPS HIS) Characteristics
Milder form of Hurler Syndrome
52
Hunter Syndrome (MPS II) L,D,MOI
Location: Lysosome Defect: Lysosomal storage disease - deficiency of iduronodate sulphatase Mode of Inheritance: X-linked recessive
53
Hunter Syndrome (MPS II) Mechanism
Deficient iduronodate sulphatase  accumulation of dermatan sulphate & heparan sulphate (GAGs)
54
Hunter Syndrome (MPS II) Characteristics
Characteristics: Similar to Hurler, BUT – later presentation (2-4 years old) and milder course, surviving into mid 30s, no corneal clouding Key words: iduronodate sulphatase, no corneal clouding **BE ABLE TO DISTINGUISH FROM HURLER - hunter needs to see to aim for the X
55
``` Sanfilippo Syndrome (MPS III) L,D,MOI ```
Location: Lysosomes Defect: Lysosomal storage disease - defect in heparan sulphate (GAG) degradation by other enzymes (type A-D) Mode of Inheritance: Autosomal recessive
56
Sanfilippo Syndrome (MPS III) Mechanism
Mechanism: Accumulation of heparan sulfate
57
Sanfilippo Syndrome (MPS III) Characteristics
Characteristics: normal development until 1-2 years  progressive mental retardation & behavioral disturbance (aggressive, destructive), hearing loss, death late teens/early 20s Key words: aggressive behavior, similar to Hurler [Note: Hurler is the most severe MPS, but children with Sanfilippo live longer with more severe behavioral problems]
58
Morquio Syndrome (MPS IV) L,D,MOI
Location: Lysosome Defect: Lysosomal storage disease - defective degradation of keratan sulphate (GAG) Mode of Inheritance: Autosomal recessive
59
Morquio Syndrome (MPS IV) Mechanism
Mechanism: Accumulation of GAG
60
Morquio Syndrome (MPS IV) Characteristics
Characteristics: normal IQ, short stature, pectus carinatum (pigeon chest), aortic regurgitation  cardiomegaly, deafness, weakness Key words: short, pectus carinatum, normal IQ; Often mistaken for skeletal dysplasia rather than lysosomal storage disease
61
Maroteaux-Lamy Sydrome (MPS VI) L,D,MOI
Deficient arylsulphatsae B (do not need to memorize for Block III) Location: Lysosome Mode of Inheritance: Autosomal recessive
62
Maroteaux-Lamy Sydrome (MPS VI) Mechanism
Mechanism: Accumulation of GAG
63
Maroteaux-Lamy Sydrome (MPS VI) Characteristics
Characteristics: Similar to Hurler, but with normal IQ, corneal opacification Key words: Similar to Hurler with normal IQ
64
Sly Syndrome (MPS VII) L,D,MOI
Location: Lysosome Defect: Deficient beta-glucoronidase (do not need to memorize for Block III) Mode of Inheritance: Autosomal recessive
65
Sly Syndrome (MPS VII) Mechanism
Mutated CHS1/LYST: delayed fusion of phagosome with lysosome in leukocytes & granular defects in NK cells  recurrent infections; granular defects in platelets  coag. defects; autophagocytosis of melanosomes in melanocytes  albinism
66
Sly Syndrome (MPS VII) Characteristics
Characteristics: Recurrent infections (life threatening), hypopigmentation, mild coagulation defects, varying neurological problems; Treatment = BMT (hematologic & immune defects) NOTE: USMLE  defect in microtubule polymerization that causes defects in cytoplasmic granules – Must know both causes! Key words: CHS1/LYST, phagocytosis, autophagocytosis, recurrent infections
67
Guacher Disease L,D,MOI
Location: lysosome Defect: Glucocerebroside (sphingolipid) Mode of Inheritance: Autosomal recessive
68
Guacher Disease Mechanism
Mechanism: Accumulation of glucocerebroside (sphingolipid); mostly occurs in macrophages
69
Guacher Disease Characteristics
Characteristics: Similar symptoms to other lysosomal storage diseases, but GAGs are not affected
70
Chediak-Higashi Syndrome L,D,MOI
Location: Lysosmoe Defect: Mutation CHS1/LYST (lysosomal trafficking regulatory protein involved in vesicle fusion) Mode of Inheritance: Autosomal recessive
71
Chediak-Higashi Syndrome Mechanism
Mutated CHS1/LYST: delayed fusion of phagosome with lysosome in leukocytes & granular defects in NK cells  recurrent infections; granular defects in platelets  coag. defects; autophagocytosis of melanosomes in melanocytes  albinism
72
Chediak-Higashi Syndrome Characteristis
Characteristics: Recurrent infections (life threatening), hypopigmentation, mild coagulation defects, varying neurological problems; Treatment = BMT (hematologic & immune defects) NOTE: USMLE  defect in microtubule polymerization that causes defects in cytoplasmic granules – Must know both causes! Key words: CHS1/LYST, phagocytosis, autophagocytosis, recurrent infections
73
Gout L,D,MOI
Location: Peroxisomes Defect: Accumulation of uric acid crystals Mode of Inheritance:
74
Gout Mechanism
Mechanism: Xanthine oxidase catalyzed hypoxanthine  xanthine  uric acid reactions; Hyperuricemia  crystallization of uric acid  deposition of crystals in joints (i.e. big toe)  destroys surrounding tissue
75
Gout characteristics
Characteristics: Inflammation of big toe due to deposits of uric acid crystals; can be treated with Allopurinaol – xanthine oxidase inhibitor  inhibits degradation of purines to uric acid Key words: hyperuricemia, Allopurinol
76
Zellweger Syndrome L,D,MOI
Location: Peroxisome PEX mutation = defected Peroxin Mode of Inheritance: Autosomal recessive, congenital
77
Zellweger Syndrome Mechanism
Defected Peroxin does not recognize SKL  failure to import peroxisomal enzymes  empty peroxisomes  peroxisome deficiency: VLCFA accumulation glial cell membrane  abnormal brain development  neuronal migration defects & hypomelination (lack of plasmalogen); accumulation of VLCFA in liver  hepatomegaly & liver failure; lack of bile acids  decreased fat absorption  decreased ATP  muscle weakness
78
Zellweger Syndrome Characteristics
Characteristics: neurological dysfunction: hypotonia, hyporeflexia, seizures, mental retardation, dysphagia; Dysmorphic features: prominent forehead, hypertelorism, large fontanelles; hepatomegaly & liver dysfunction; death 6-12 months Key words: peroxins don’t recognize SKL, accumulation of VLCFA, hepatomegaly, prominent forehead, large fontanelles, lack of plasmalogen
79
X-linked Adrenoleukodystrophy (XALD) L,D,MOI
Location: Peroxisomes Defect: VLCFA import protein defect (not peroxin) Mode of Inheritance: X-linked
80
X-linked Adrenoleukodystrophy (XALD) Mechanism
Mechanism: Defect in transport of VLCFA into peroxisome  defective breakdown of VLCFAs  accumulation of VLCFA: brain (glial cells)  myelin breakdown; adrenal cortex  adrenal atrophy
81
X-linked Adrenoleukodystrophy (XALD) Characteristics
Characteristics: progressive; onset 5-10 years old: apathy, behavioral changes; spasticity, ataxia, visual loss, death few years later Key words: VLCFA transport defect, glial accumulation, myeline breakdown, adrenal atrophy, behavioral changes, most common peroxisomal disorder
82
Barth Syndrome L,D,MOI
Location: Mitochondria Defect: Defect in cardiolipin synthesis Mode of Inheritance: X-linked
83
Barth Syndrome Mechanism
Mechanism: Defect in cardiolipin synthesis  disorganized mitochondrial inner membrane  lack of structure & permeability  inefficient ATP synthesis
84
Barth Syndrome Characteristics
Characteristics: SIDS, cardiomyopathy, generalized muscle weakness, chronic fatigue, neutropenia Key words: cardiolipin synthesis, SIDS, high mortality in infants
85
Progressive External Ophtalmoplegia (PEO) L,D,MOI
Location: Mitochondria Defect: Mutation in POLG or mutation in TWINKLE gene for mt helicase Mode of Inheritance: Autosomal dominant
86
Progressive External Ophtalmoplegia (PEO Mechanism
Mechanism: mtDNA depletion or multiple large deletions in the mtDNA
87
Progressive External Ophtalmoplegia (PEO) Characteristics
Characteristics: Bilateral ptosis – progressive weakening of external eye muscles, proximal muscle weakness and wasting, exercise intolerance Key words: bilateral ptosis, mtDNA depletion/deletion, polymerase gamma
88
Kearns-Sayre Syndrome (KSS) L,D,MOI
Location: Mitochondria Defect; Giant mtDNA deletion (DNA pol gamma) Mode of Inheritance: Mitochondrial
89
Kearns-Sayre Syndrome (KSS) Mechanism
Mechanism: Giant mtDNA deletion in muscle – no bone marrow involvement
90
Kearns-Sayre Syndrome (KSS) Characteristics
Characteristics: late onset, typical ragged red fibers (>80% mutated mtDNA), PEO, retinopathy, cerebellar ataxia, heart block Key words: no bone marrow involvement, late onset, ragged red fibers
91
Pearson Syndrome L,D,MOI
Location: Mito Defect: Giant mtDNA deletion (DNA pol gamma) Mode of Inheritance: Mitochondrial
92
Pearson Syndrome Mechanism
Mechanism: Giant mtDNA deletions
93
Pearson Syndrome Characteristics
Characteristics: Pancytopenia – all tissues have mtDNA with deletions, sideroblastic anemia, exocrine pancreatic failure Key words: pediatric disease, bone marrow involvement, pancytopenia [Note: Some Pearson Syndrome patients that survive undergo phenotype switching to Kearns-Sayre Syndrome]
94
MELAS (Mitochondrial Encephalomyopathy, Lactic Acidosis, Stroke-like episodes) L,D,MOI
Location: mito Defect: Mutated tRNALeu (point mutation) Mode of Inheritance: Maternally transmitted
95
MELAS (Mitochondrial Encephalomyopathy, Lactic Acidosis, Stroke-like episodes) Mechanisms
Mechanism: mt tRNA deletion; always heteroplasmic
96
MELAS (Mitochondrial Encephalomyopathy, Lactic Acidosis, Stroke-like episodes) Characteristcs
Characteristics: short stature, stroke-like episodes (vomiting, headaches, visual disturbances), diabetes, sensorineural hearing loss Key words: tRNALeu, short, stroke, diabetes
97
MERRF (Myoclous Epilepsy and Ragged Red Fibers) L,D,MOI
Location: Mito Defect: Mutated tRNALys Mode of Inheritance: Maternally transmitted
98
MERRF (Myoclous Epilepsy and Ragged Red Fibers) Mechanism
Mechanism: mt tRNA deletion; always heteroplasmic
99
MERRF (Myoclous Epilepsy and Ragged Red Fibers) Characteristics
Characteristics: progressive myoclonic epilepsy and seizures Key words: tRNALys, ragged red fibers, epilepsy
100
LHON (Leber’s Hereditary Optic Neuropath) L,D,MOI
Location: Mito Defect: Missense mutations of subunits of Complex I (subunits 4, 6, 1) Mode of Inheritance: Maternally transmitted
101
LHON (Leber’s Hereditary Optic Neuropath) Mechanism
Mechanism: mt mRNA mutation; can be homoplasmic – optic nerve is only affected tissue
102
LHON (Leber’s Hereditary Optic Neuropath) Characteristics
Characteristics: subacute painless bilateral visual failure, male:female 4:1 (X-chromosome penetrance), ~24 years old Key words: mutated Complex I gene, optic nerve damage, homoplasmy, bilateral vision failure
103
NARP (Neurogenic muscle weakness, Ataxia, and Retinitis Pigmentosa) L,D,MOI
Location: Mito Defect: Mutated ATPase 6 gene (subunit of Complex V) Mode of Inheritance: Maternally transmitted
104
NARP (Neurogenic muscle weakness, Ataxia, and Retinitis Pigmentosa) Mechanism
Mechanism: mt mRNA mutation; always heteroplasmic
105
NARP (Neurogenic muscle weakness, Ataxia, and Retinitis Pigmentosa) Characteristics
Characteristics: late childhood or adult onset peripheral neuropathy, ataxia, pigmentary retinopathy Key words: ATPase 6 gene, ataxia, retinopathy, pigmentation, Leigh Syndrome Note: Maternally inherited Leigh Syndrome is a more severe form with a larger portion of mutated mtDNA

Disease MCB (1 decks)

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