M2M Unit 2 Flashcards

1
Q

CYP3A

A

Substrates: Cyclosporine mechanism: genetically less important than other drug metabolism genes b/c activity continuous and unimodal Inhibitors: Ketoconazole, grapefruit juice inducers: Rifampin

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2
Q

CYP2D6

A

Substrates: Tricyclic antidepressants and codeine (activates codeine->morphine) Inhibitors: Quinidine, Fluoxetine, Paroxetine Whites poor metabolizers

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3
Q

CYP2C9

A

Substrates: Warfarin use VKORC1 as marker to approx. target dose underdose-> clot; overdose-> bleed 20% Whites need lower dose–> poor metabolizers

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4
Q

NAT

A

Drugs: Isoniazid for TB mechanism: rate of acetylation determined by genetic polymorphism comments: Important in Phase II pathway -Modifies risk of cancers though differences in acetylation of carcinogens

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5
Q

TMPT

A

Drugs: 6-mercaptopurine, 6-thioguanine 5% of kids with ALL (leukemia) poor metabolizers (absent activity)–> will KILL child (immunosuppression) if don’t test for it (functional assay) Solution: give lower dose

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6
Q

G6PD

A

Substrates: Sulfonamide antibiotics, dapsone Mechanism: X-linked enzyme -Deficient individuals susceptible to hemolytic anemia after sulfa or dapsone drug exposures

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7
Q

VKORC1

A

Drug: Warfarin Mechanism: reduces vit. K; single nucleotide polymorphism –Warfarin is a ‘blood thinner” one of the most commonly prescribed meds given to >20,000,000 pts. in the US/year

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8
Q

Trisomy 21

A

Down syndrome

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9
Q

45, X

Short, webbed neck, borad chest, infertility

A

Turner syndrome

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10
Q

tall, hypogonadism, sterility, lang. impairment, gynecomastia

A

Klinefelter syndrome

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11
Q

47, XXY

A

Klinefelter syndrome (tall, hypogonadism, sterility, lang. impairment, gynecomastia)

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12
Q

47, XXY look like normal males increased behavioral and educational problems

A

XXY syndrome

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13
Q

characteristic facies, CNS ab., Facial cleft, polydactyly, Congenital heart disease, etc.

A

Patau Syndrome

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14
Q

47, XX, +13

A

Patau Syndrome (characteristic facies, CNS ab., Facial cleft, polydactyly, Congenital heart disease, etc.)

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15
Q

growth retardation, Hypertonicity, Seizures, ID severe

A

Edwards syndrome

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16
Q

47, XX, +18

A

Edwards syndrome (growth retardation, Hypertonicity, Seizures, ID severe)

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17
Q

46, XX, t(9;22) (q34;q11.2)

A

Cronic Myelogenous leukemia (reciprocal translocation) anemia

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18
Q

46, XX, der(14;21)(q10;q10), +21

A

Down syndrome (robertsonian translocation)

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19
Q

46, XY, del(5)(p15)

A

cri-du-chat syndrome (deletion)

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20
Q

46, XX, i(21)(21q21q)

A

Down syndrome (Isochromosomes)

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21
Q

weakness in legs, lower extremity muscle atrophy, foot deformity, some loss of sensation in feet

A

Charcot-marie-tooth disease duplication of gene for peripheral myelin protein-22

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22
Q

46, XX, dup(17p11.2)

A

Charcot-marie-tooth disease duplication of gene for peripheral myelin protein-22 (contiguous gene syndromes/ “genetic” disorders)

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23
Q

46, XX, del(17p11.2)

A

Hereditary neuropathy with liability to pressure palsies -deletion of the gene encoding peripheral myelin protein-22 (contiguous gene syndromes/”genetic” disorders)

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24
Q

25yo with foot drop, loss of sensation in legs for days to months.

A

Hereditary neuropathy with liability to pressure palsies -deletion of the gene encoding peripheral myelin protein-22 (AD)

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25
Q

Cleft palate, septal defects

A

Velocardiofacial syndrome

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26
Q

del 22q11

A

Velocardiofacial syndrome (cleft palate, septal defects)

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27
Q

del 22q11

neural crest, cranchial pouches, great vessels, outflow tract defects in heart

A

DiGeorge Syndrome

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28
Q

Initially not eating well on own now 3 yo is obese and will eat all the time. behavioral issues and a little slow to learn in school

A

Prader-Willi

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29
Q

del(15)(q11-13) paternal

A

Prader-Willi

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30
Q

developmentally delayed, tremulous movement of limbs, language impairment, hand flapping, happy demeanor, seizures when <3yo, misaligned eyes (strabismus)

A

Angelman syndrome

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31
Q

del(15)(q11-q13) maternal

A

Angelman syndrome

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32
Q

Interstitial duplication on chr 15

A

autism/ hypotonia/seizures/ID

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33
Q

Marker chr-inverted duplicaiton on chr 15

A

autism/hypotonia/seizures (supernumery marker chr)

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34
Q

t(15;17)(q22;q21)

A

Acute Myeloid Leukemia (fusion of PML-RARalpha)

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35
Q

t(8;22)(q34;q11)

A

Acute Myeloid Leukemia (fusion of Abl1;BCR)

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36
Q

t(9;22)(q34;q11.2)

A

Chronic myeloid leukemia (night sweats, fatigue, weight loss, anemia) treatment: GLEEVEC

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37
Q

46, XY Phenotypes range from mild under-virilization to full sex reversal

A

Androgen Insensitivity Syndrome (AIS)

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38
Q

46, XY Phenotype shows undervirilized male with increased virilization at the time of puberty

A

5-Alpha Reductase Deficiency

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39
Q

46, XY Deletion or absence of SRY

A

sex reversal and a phenotypically normal female

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40
Q

46, XX Ectopic presence of the SRY gene

A

individual results in a phenotypically normal male

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41
Q

46, XY mutation in WT1 gene

A

Denys-Drash & Frasier Syndrome sex reversal, chronic kidney disease

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42
Q

Ambiguous genitalia and salt wasting in first few weeks of life in 46, XX

A

Congenital Adrenal Hyperplasia

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43
Q

tall, female, seizures, LD, delayed speech, variable expressivity

A

Triple X syndrome

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44
Q

47 XXX

A

Triple X syndrome (tall, female, seizures, LD, delayed speech)

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45
Q

Male, LD, behavioral issues, tall, developmental delays, autism

A

Jacobs Syndrome, 47 XYY

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46
Q

47, XYY

A

Jacobs Syndrome (Male, LD, behavioral issues, tall, developmental delays, autism)

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47
Q

Turner syndrome

A

45, XO (short, webbed neck, broad chest)

48
Q

Klinefelter syndrome

A

47, XXY (tall, hypogonadism, sterility, lang. impairment, gynecomastia)

49
Q

XXY syndrome

A

47, XXY look like normal males increased behavioral and educational problems

50
Q

Patau Syndrome

A

46, XX, +13 (characteristic facies, CNS ab., Facial cleft, polydactyly, Congenital heart disease, etc.)

51
Q

Edwards syndrome

A

46, XX, +18 (growth retardation, Hypertonicity, Seizures, ID severe)

52
Q

Cronic Myelogenous leukemia

A

46, XX, t(9;22) (q34;q11.2)

53
Q

cri-du-chat syndrome

A

46, XY, del(5)(p15)

54
Q

Charcot-marie-tooth disease

A

46, XX, dup(17p11.2) duplication of gene for peripheral myelin protein-22 (contiguous gene syndromes/ “genetic” disorders)

55
Q

Hereditary neuropathy with liability to pressure palsies

A

46, XX, del(17p11.2) -deletion of the gene encoding peripheral myelin protein-22 (contiguous gene syndromes/”genetic” disorders)

56
Q

Velocardiofacial syndrome

A

del 22q11 (cleft palate, septal defects)

57
Q

DiGeorge Syndrome

A

del 22q11 (neural crest, cranchial pouches, great vessels, outflow tract defects in heart)

58
Q

Prader-Willi

A

del(15)(q11-13) paternal

59
Q

Angleman Syndrome

A

del(15)(q11-13) maternal

60
Q

Acute Myeloid Leukemia

A

t(15;17)(q22;q21) or t(8;22)(q34;q11)

61
Q

Chronic myeloid leukemia

A

t(9;22)(q34;q11.2) (night sweats, fatigue, weight loss, anemia) treatment: GLEEVEC

62
Q

Androgen Insensitivity Syndrome (AIS)

A

46, XY Phenotypes range from mild under-virilization to full sex reversal

mutation of androgen receptor

63
Q

5-Alpha Reductase Deficiency

A

46, XY Phenotype shows undervirilized male with increased virilization at the time of puberty

64
Q

Denys-Drash & Frasier Syndrome

A

46, XY mutation in WT1 gene sex reversal, chronic kidney disease

65
Q

Congenital Adrenal Hyperplasia

A

Ambiguous genitalia in 46, XX (Complicated by salt wasting in the first few weeks of life)

66
Q

Triple X syndrome

A

47 XXX (tall, seizures, LD, delayed speech)

67
Q

Jacobs Syndrome

A

47 XYY (LD, behavioral issues, tall, developmental delays, autism)

68
Q

Skeletal dysplasia, Rhizomelic limb shortening, small stature, trident hands, short fingers, large head/frontal bossing

A

Achodroplasia

Mutation: FGFR3 (fibroblast growth factor receptor 3) Amino acid substitution GtoA Mutation increases activity of the protein interfering with skeletal devo. Paternal age effect

69
Q

Achodroplasia

A

Complete penetrance, AD De novo mutations

Clinical: Skeletal dysplasia, Rhizomelic limb shortening, small stature, trident hands, short fingers, large head/frontal bossing

AA=lethal

Mutation: FGFR3 (fibroblast growth factor receptor 3) Amino acid substitution GtoA Mutation increases activity of the protein interfering with skeletal devo. Paternal age effect

70
Q

Diseases with reduced penetrance

A

Retinoblastoma

BRCA mutation

Huntington disease

71
Q

Retinoblastoma

A

Reduced penetrance, AD

Clinical: malignant tumor of retina

Mutation: RB1 on chr. 13 protein regulates cell cycle 90% penetrance

72
Q

Disease with variable expressivity

A

Neurofibromatosis Type 1

Osteogenesis Imperfecta Type 1

73
Q

Neurofibromatosis Type 1

A

Variable expressivity, AD

need two or more criteria:

>6 cafe-au-lait spots

>2 neurofibromas plexiform

neuro fibroma

optic glioma

>2 lisch nodules

affected 1st degree relative

Mutation: NF1 tumor supressor gene LOF must have mut. in both genes to show phenotype even though considered AD

74
Q

Osteogenesis Imperfecta Type 1

A

variable expressivity, AD

Clinical: multiple fracture Blue sclera, mild short stature, adult onset hearing loss.

Mutation: COL1A1 (collagen type 1 alpha 1) reduced production of pro alpha 1 chains–> reduce type 1 collagen production

75
Q

Marfan Syndrome

A

AD Clinical: systemic disorder of connective tissue in eye, skeletal, cardio Diagnosis: aortic root enlargement, ectopia lentis, systemic score >7 Mutation: FBN1 (fibrillin extracellular matrix protein) dominant negative activity mut. reduce # of microfibrils

76
Q

Bilateral renal cysts cysts in other organs vascular abnormalities End stage renal disease 50% of 60yo

A

Autosomal Dominant Polycystic Kidney Disease

AD, Locus heterogeneity

Mutation: PKD1 (chr 16p13.3) PKD2 (chr 4q22.1) polycystin 1 and 2 Truncated protein

77
Q

Autosomal Dominant Polycystic Kidney Disease

A

AD, Locus heterogeneity Clinical: Bilateral renal cysts cysts in other organs vascular abnormalities End stage renal disease 50% of 60yo Mutation: PKD1 (chr 16p13.3) PKD2 (chr 4q22.1) polycystin 1 and 2 Truncated protein

78
Q

High cholesterol and LDL levels, Xanthomas (fat build up under skin), premature coronary artery disease and death

A

Familial Hypercholesterolemia

AD, Locus heterogeneity

Mutation: 3 genes LDLK (highest rate), APOB, PCSK9

79
Q

Familial Hypercholesterolemia

A

AD, Locus heterogeneity

Clinical: High cholesterol and LDL levels Xanthomas premature coronary artery disease and death Mutation: 3 genes LDLK (highest rate), APOB, PCSK9

80
Q

neuronal degeneration onset at 35-44 yo death ~15 yrs after onset, jerking movements, halucinations, father died young, irritability, paranoia and later on confusion and memory loss.

A

Huntington Disease

AD, Trinucleotide repeat disorder (CAG) Anticipation, paternal transmission

Mutation: HTT (huntingtin) Chr 4p16.3 expansion of the CAG can cause altered structure of protein

81
Q

Huntington Disease

A

AD, Trinucleotide repeat disorder (CAG) Anticipation, paternal transmission

Clinical: neuronal degeneration onset at 35-44 yo death ~15 yrs after onset

Mutation: HTT (huntingtin) Chr 4p16.3 expansion of the CAG can cause altered structure of protein

82
Q

muscular dystrophy, progressive muscle wasting and weakness, myotonia, cataracts

A

Myotonic Dystrophy Type 1

AD, Trinucleotide repeat disorder (CTG) located in 3’ UTR

anticipation, maternal transmission

Mutation: DMPK (myotonic dystrophy protein kinase) plays important roll in muscle, heart and brain cells.

83
Q

Myotonic Dystrophy Type 1

A

AD, Trinucleotide repeat disorder (CTG) located in 3’ UTR

anticipation, maternal transmission

Clinical: muscular dystrophy progressive muscle wasting and weakness, myotonia, cataracts

Mutation: DMPK (myotonic dystrophy protein kinase) plays important roll in muscle, heart and brain cells.

84
Q

autism/ hypotonia/seizures/ID

A

Interstitial duplication on chr 15

85
Q

autism/hypotonia/seizures (supernumery marker chr)

A

Marker chr-inverted duplicaiton on chr 15

86
Q

malignant tumor of retina

A

Retinoblastoma

Reduced penetrance, AD

Mutation: RB1 on chr. 13 protein regulates cell cycle 90% penetrance

87
Q

multiple cafe-au-lait spots, neurofibromas plexiform, optic glioma, multiple lisch nodules

A

Neurofibromatosis Type 1

Variable expressivity, AD

Mutation: NF1 tumor supressor gene LOF must have mut. in both genes to show phenotype even though considered AD

88
Q

multiple fractures, Blue sclera, mild short stature, adult onset hearing loss.

A

Osteogenesis Imperfecta Type 1

variable expressivity, AD

Mutation: COL1A1 (collagen type 1 alpha 1) reduced production of pro alpha 1 chains–> reduce type 1 collagen production

89
Q

systemic disorder of connective tissue in eye, skeletal, cardio, aortic root enlargement, ectopia lentis, systemic score >7

A

Marfan Syndrome

Mutation: FBN1 (fibrillin extracellular matrix protein) dominant negative activity mut. reduce # of microfibrils

90
Q

X-linked Dominant Disorders

A

Hypophosphatemic Rickets Fragile X Syndrome Charcot Marie Tooth Incontinentia pigmenti rett syndrome Orofacicodigital syndrome focal dermal hypoplasia

91
Q

Hypophosphatemic Rickets

A

X-linked Dominant PHEX, regulates fibroblast GF inhibits the kidneys ability to reabsorb phosphate into blood

92
Q

Hypophosphatemia, short stature, bone deformity

A

Hypophosphatemic Rickets X-linked Dominant Mutation: PHEX, regulates fibroblast GF inhibits the kidneys ability to reabsorb phosphate into blood

93
Q

Fragile X Syndrome

A

X-linked dominant Trinucleotide repeat disorder CGG (in 5’UTR region) Anticipation, Maternal transmission Clinical: ID, dysmorphic features (large ears, long face, macroorchidism), Autism, Social anxiety, hand flapping/biting, aggression Mutation: FMR1 (protein essential for normal cognitive devo and female repo. function increase trinucleotide repeat number methylate gene–> LOF

94
Q

ID, dysmorphic features (large ears, long face, macroorchidism), Autism, Social anxiety, hand flapping/biting, aggression

A

Fragile X Syndrome X-linked dominant Trinucleotide repeat disorder CGG (in 5’UTR region) Mutation: FMR1 (protein essential for normal cognitive devo and female repo. function increase trinucleotide repeat number methylate gene–> LOF

95
Q

Rett Syndrome

A

X-linked Dominant Clinical: Loss of normal movement and coordination, loss of communication skills, failure to thrive, Seizures, abnormal hand movements Mutation: MECP2 (methyl CpG binding protein) essential for the normal function of nerve cells

96
Q

Loss of normal movement and coordination, loss of communication skills, failure to thrive, Seizures, abnormal hand movements

A

Rett Syndrome X-linked Dominant Mutation: MECP2 (methyl CpG binding protein) essential for the normal function of nerve cells

97
Q

X-linked Recessive Disorders

A

Lesch-Nyhan Syndrome Dystrophinopathies Hunter’s Disease Menaces Disease Glucose 6 phosphate dehydrogenase deficiency Hemophilia A and B Wiscott Aldrich Syndrome Colorblindness

98
Q

Lesch-Nyhan Syndrome

A

X-linked recessive Clinical: Neurological and behavioral abnormalities, overproduction of uric acid, self injury Mutation: HPRT1 recycling of purines

99
Q

Neurological and behavioral abnormalities, overproduction of uric acid, self injury

A

Lesch-Nyhan Syndrome X-linked recessive Mutation: HPRT1 recycling of purines

100
Q

Dystrophinopathies

A

X-linked recessive spectrum of muscle disease from mild to severe: Duchenne Muscular Dystrophy (most severe) Becker Muscular Dystrophy DMD-associated dilated cardiomyopathy mutation: DMD (dystrophin) Xp21-21.1

101
Q

Duchenne Muscular Dystrophy

A

X-linked recessive Clinical: Progressive muscular weakness (proximal to distal), calf hypertrophy, dilated cardiomyopathy, High CK levels, onset before age 5, wheelchair before age 13, death in 30s No dystrophin Mutation: DMD

102
Q

15 yo, wheelchair bound since age 13, muscle weakness, calf hypertrophy, dilated cardiomyopathy, CK levels x10

A

Duchenne Muscular Dystrophy X-linked recessive

103
Q

Becker Muscular Dystrophy

A

X-linked recessive Clinical: Progressive muscular weakness (proximal to distal), dilated cardiomyopathy, CK levels 5x, onset later than duchenne muscular dystrophy, wheelchair bound after 16yo, death in 40s abnormal quantity or quality of Dystrophin Mutation: DMD

104
Q

20 yo, wheelchair bound since age 16, muscle weakness that developed over time, dilated cardiomyopathy, CK levels 5x

A

Becker Muscular Dystrophy X-linked recessive

105
Q

DMD-associated DCM

A

X-linked recessive Clinical: dilated cardiomyopathy presenting between 20-40 yo, early death, no skeletal muscle involved no dystrophin in myocardium Mutation: DMD

106
Q

Died around 55 after presenting with dilated cardiomyopathy at age 30

A

DMD-associated DCM

107
Q

Hemophilia A

A

X-linked recessive Clinical: Spontaneous bleeds into joints, muscles or intracranial. excessive bruising, prolonged bleeding after injury, delayed wound healing Mutation: F8 deficiency of factor VIII, chr. Xq28

108
Q

Spontaneous bleeds into joints, muscles or intracranial. excessive bruising, prolonged bleeding after injury, delayed wound healing

A

Hemophilia A X-linked recessive Mutation: F8 deficiency of factor VIII, chr. Xq28

109
Q

mycrocephaly and mental retardation, seizures, gait disorders, tremors

A

Phenylketonuria (PKU)

AR

Mutation: PAH mutation–> high levels of Phe because not converted to Tyr

110
Q

Phenylketonuria (PKU)

A

mycrocephaly and mental retardation, seizures, gait disorders, tremors

AR

Mutation: PAH mutation–> high levels of Phe because not converted to Tyr

111
Q

alpha1- Antitrypsin Deficiency (ATD)

A

increased risk of developing emphysema, late onset, increased risk of liver cirrhosis and liver cancer worse in smokers

AR

Mutation: two alleles Z and S

Z/Z= 10-15% normal activity, S/S 50-60% normal activity (no symptoms)

Biological: SERPINA1 (serine protease inhibitor) targets elastase–> neutrophils in lung

Molecular: Z allele–> misfolded protein aggragated in liver, S allele–> unstable protein less effective

112
Q

increased risk of developing emphysema, late onset, increased risk of liver cirrhosis and liver cancer worse in smokers

A

alpha1- Antitrypsin Deficiency (ATD)

113
Q

Tay-Sachs disease

A

infants appear normal until 3-6 months then get muscle weakness, decreased attentiveness, increase startle response. later get nurodegeneration–seizures, vison and hearing loss, diminished mental function, paralysis

AR (ashkenazic jews higher risk)

Biological: lysosomal storage disorder, inability to degrade Gm2 ganglioside–> accumulation in neurons of CNS.

Mutation : defective Hex A

114
Q

infants appear normal until 3-6 months then get muscle weakness, decreased attentiveness, increase startle response. later get nurodegeneration–seizures, vison and hearing loss, diminished mental function, paralysis

A

Tay-Sachs disease

AR (ashkenazic jews higher risk)

Biological: lysosomal storage disorder, inability to degrade Gm2 ganglioside–> accumulation in neurons of CNS.

Mutation : defective Hex A

115
Q

Sandhoff disease

A

Same syptoms as Tay-Sachs: muscle weakness, neurodegeneration (seizures, vision and hearing loss, diminishing mental function, “cherry-red spot” in the eyes.

AR

Mutation: Mutation of HEXB (insertion)

Biological: Dysfunctional beta subunit –> build up of Gm2 ganglioside

116
Q

AB-variant of Tay-Sachs

A

Rare

Both HexA and HexB functional but Gm2 accumulates dues to defective Gm2 activator protein