Genetics Questions

Front 1

When does ketonuria occur?

Back 1

starvation or insulin deficiency

Front 2

Klinefelter syndrome

Back 2

1 in 850 males. 47XXY. Sx= oligospermia, bilateral gynecomastia, reduced testicular size, reduced body hair.

Front 3

47XYY

Back 3

taller than average stature

Front 4

46XX/47XX+21

Back 4

Milder features of down syndrome

Front 5

47XX+21

Back 5

Down syndrome

Front 6

46XY, del(22q11)

Back 6

Congenital defects (palate, face, heart). Sometimes T-cell immunodeficiency.

Front 7

Hunter Syndrome

Back 7

Lysosomal storage disease w/ alpha-L-iduronidase deficiency. One of the MPS (mucopolysaccharidoses). Glycosaminoglycans accumulate (dermatan sulfate, heparin sulfate, keratin sulfate, condroitan sulfate). X-linked recessive. (All other MPSs are autosomal recessive).
No corneal clouding.

Front 8

McArdle Syndrome

Back 8

Muscle phosphorylase deficiency. Glycogen storage disease. Presents in young adulthood. Glycogen accumulates in skel muscle. Strenous exercise gives muscle cramps and no rise of lactic acid. Myoglobinuria seen in 50% of cases.

Front 9

Pompe disease

Back 9

Glycogen storage disease. Lysosomal glucosidase (acid maltase) deficiency. Glycogen in heart gives massive cardiomegaly and heary failure w/in 2 years.

Front 10

Cleft lip has what type of inheritance?

Back 10

Multifactorial

Front 11

Marfan syndrome inheritance?

Back 11

Autosomal dominant

Front 12

Tay-sachs disease inheritance?

Back 12

autosomal recessive (lysozomal storage disease)

Front 13

Erythroblastosis fetalis inheritance?

Back 13

Maternal sensitization against fetal RBCs.

Front 14

Polycystic kidney disease inheritance?

Back 14

dominant, recessive or sporadic mutations.

Front 15

Trisomy 13

Back 15

aka Patau syndrome. Sx= microcephaly, cleft lip/palate, six fingers (polydactyly), severe congenital heart malformation.

Front 16

Downs syndrome
-another name
-disease complications

Back 16

trisomy 21. Often congenital HD (ventricular septal defect), 10-20x acute leukemia risk. Alzheimers common if reach 40y/o.

Front 17

Aortic dissection is common in patients with?

Back 17

Marfans syndrome

Front 18

Trisomy 21 hand features?

Back 18

single palmar flexion crease and single flexion crease on fifth digit

Front 19

Monosomy X hand features?

Back 19

short fourth metacarpal

Front 20

trisomy 18 hand features?

Back 20

fingers clenched, digits 2 and 5 overlapping 3 and 4

Front 21

triploidy hand features?

Back 21

syndactyly of digits 3 and 4.

Front 22

Back 22

Turners syndrome

Front 23

another term for turner syndrome?

Back 23

monosomy X

Front 24

What is another name for trisomy 18?

Back 24

Edwards syndrome

Front 25

Trisomy 18 clinical signs

Back 25

* mental retardation/delayed development (100%), high muscle tone, seizures.
* small head (microcephaly), small eyes, wide-set eyes, epicanthal folds, small lower jaw
* Congenital heart defects (90% of individuals) such as ventricular septal defect and valve defects
* Severe growth retardation, clenched hands with 2nd and 5th fingers on top
* Malformations of the digestive tract, the urinary tract, and genitals

Front 26

Fragile X syndrome
- inheritance

Back 26

X-linked recessive.

Front 27

Fragile X syndrome
-gene?

Back 27

Trinucleotide repeat disorder (CGG).
Affects methylations and expression of fragile X mental retardation protein 1 (FMRP1). Associated w/ chromo breakage.

Front 28

Fragile X syndrome
-Sx

Back 28

Mental retardation, macroorchidism (large testes), speech delay, behavior problems (ADHD), prominent forehead and jaw, joint laxity, large, dysmorphic ears, autism. Fragile X= eXtra large testes, jaw, ears

Front 29

What is the first and second leading causes of inherited mental retardation?

Back 29

Down's syndrome (#1) and Fragile X

Front 30

Friedreich ataxia (FRDA)
-inheritance

Back 30

autosomal recessive

Front 31

Friedreich ataxia
-- gene?

Back 31

FXN gene on chromo 9q13-a21.1 for the frataxin protein.
Caused by unstable repeats of GAA.
** Highly expanded repeats outside the gene disease **

Front 32

Friedreich ataxia
--role of altered protein?

Back 32

Frataxin protein.
Plays role in respiratory chain complexes I-III, mitochondrial iron content and antioxidation defense.

Front 33

Friedreich ataxia
--Sx

Back 33

Degeneration of posterior column and spinocerebellar tracts. Sensory neuron loss in DRG. Limb ataxia. optic nerve atrophy, scoliosis, bladder dysfunction, swallowing dysfunction, pyramidal tract disease, cardiomyopathy and diabetes.

Front 34

Myotonic Dystrophy Type 1
-- inheritance?

Back 34

autosomal dominant. Caused by unstable CTG repeat sequence. on DMPK gene in chromo 19q13.2-q13.3 for myotonin-protein kinase.

Front 35

Myotonic Dystrophy Type 1
--role of altered protein?

Back 35

myotonin-protein kinase= protein.
intercellular conduction and impulse transmission in heart and skeletal muscles.

Front 36

Myotonic Dystrophy Type 1
-Sx

Back 36

muscle weakness, wasting myotonia (delayed relaxation after contraction), cataracts, cardiomyopathy w/ conduction defects, mult. endocrinopathies, low IQ/dementia.

Front 37

Spinocerebellar ataxias
-inheritance

Back 37

autosomal dominant. -repeat sequences.

Front 38

Spinocerebellar ataxias
-Sx

Back 38

increasing cerebellar ataxias.

Front 39

List 4 diseases or syndromes caused by HIGHLY EXPANDED repeats outside the gene

Back 39

Fragile X, Freidrich ataxia, Myotonic dystrophy type 1, Spinocerebellar ataxias (8 and 11)

Front 40

List 3 diseases or syndromes caused by moderately expanded CAG repeats inside the gene

Back 40

Huntington's disease, spinal and bulbar muscular atrophy, spinocerebellar ataxia type 3.

Front 41

Describe the pathogenesis of moderately expanded repeats inside the gene

Back 41

CAG repeat (glutamine) undergoes moderate expansions. Long tract of glutamines (polyglutamine tract) is inserted into the protein and causes aggregation.

Front 42

Spinal and Bulbar Muscular Atrophy
-inheritance?

Back 42

X-linked recessive in the coding sequence of AR gene on chromo Xq11-q12 for androgen receptor; likely gain of function mutation.

Front 43

Spinal and Bulbar Muscular Atrophy
-Sx

Back 43

progressive anterior motor neuron loss, proximal muscle weakness, muscle atrophy, muscle fasciculations, difficulty swalling and speech articulation, late-onset gynecomastia, defective speramtogenesis w/ reduced fertility, testicular atrophy and hormonal profile consistent w/ androgen resistance.

Front 44

Spinocerebellar ataxia type 3
-Inheritance

Back 44

Autosomal dominant w/ CAG (glutamine) repeat in coding sequence of ATXN3 gene fror ataxin 3 protein which is a ubiquitin-specific protease that binds and cleaves ubiquitin chains (thus acts as protein quality control). Thus SCA3 thought to be caused by impaired protein clearance.

Front 45

Spinocerebellar ataxia type 3
-Sx

Back 45

progressie cerebellar ataxia, dysarthria, bulbar dysfunction, extrapyramidal features (rigidity, dystonia), upper/lower neuron signs, cognitive impairments. onset= 20-50y/o.
nuclear inclusions seen.

Front 46

Marfan's Syndrome
-Mutation, type of disease
-Sx

Back 46

fibrillin gene mutation.
connective tissue disorder affecting skeleton, heart and eyes.
Sx= tall, long extremities, pectus excavatum, lax joints, long tapering fingers and toes, aortic dissection, floppy mitral valve, lens subluxation.

Front 47

Back 47

marfan's syndrome
fibrillin gene mutation (CT disorder).
affects skeleton, heart and eyes.