Genetics

Question 1

Marfan Syndrome

Answer 1

Tall, long arms, pectus excavatum, scoliosis, lens dislocaiton. Defect in Fibrillin-1. Aortic Root Dilatation is the most severe complication.

Question 2

Ehlers-Danlos Syndrome

Answer 2

Normal stature, scoliosis, joint laxity, aortic root dilatation. Collagen disorder.

Question 3

Duchenne Muscular Dystrophy

Answer 3

Calf pseudohypertrophy
Gower Sign
Dx with genetic testing
Xlink recessive

Question 4

Osteogenesis imperfecta

Answer 4

90% Autosomal dominant, type I collagen defect

Mild-Moderate type: easy fractures, blue sclera, gray teeth, joint hypermobility, conductive hearing loss

Lethal type:in utero/neonatal fractures, pulmonary failure

Question 5

Tay-Sachs Disease

Answer 5

B-hexosaminidase A deficiency, autosomal recessive, Ashkenazi Jews.
Hypotonia, feeding difficulty, Hyperreflexia, Cherry Red Macula
2-6mo age of onset

Question 6

Niemann-Pick Disease

Answer 6

Sphingomyelinase Deficiency, autosomal recessive, Ashkenazi Jews.
Hypotonia, Feeding difficulties, HSM, Areflexia, Cherry red macula.
2-6mo age of onset.

Question 7

Fragile X Syndrome

Answer 7

Neurodevelopmental problems, prominent forehead, large ears, elfin like face, macroochidism.
X linked CGG expansion in FMR1 gene.
Females will have varying levels of intellectual disability

Question 8

Edward Syndrome

Answer 8

Trisomy 18
IUGR, microcephaly, VSD, overlapping fingers, rocker bottom heels, micrognathia, low set ears, prominent occiput, renal dysfunction, limited hip abduction.
95% die in the first year of life.

Question 9

Cri-du-chat

Answer 9

5p deletion

cat-like cry, prominent metopic suture, hypertelorism, microcephaly, intellectual diability.

Question 10

Patau Syndrome

Answer 10

Trisome 13
Cutis aplasia, holoprosencephaly, microphthalmia, cleft lip and palate, polydactyly, cardiac defects, renal defects, omphalocele, and rocker bottom heels.

Question 11

Choanal Atresia

Answer 11

Incomplete recanalization of the nasal passages. Infants will be cyanotic at rest, improve when crying, and have difficulty feeding.

This can be a sole finding or present with CHARGE syndrome

Question 12

CHARGE Syndrome

Answer 12

Choloboma (eye defect), Heart Defects, Atresia chonae, Retardation, Genitourinary problems, Ear Abnormalities/Deafness

Question 13

Cystinuria

Answer 13

stones since childhood, FMH of nephrolithiasis, hexagonal crystals in urine.

impaired transport of cystine.
+ cyanide-nitroprusside test

Question 14

Common Variable Deficiency

Answer 14

Recurrent infections starting in middle childhood

markedly decrease IgG, moderately decrease IgM and IgA.
Normal T and B cell counts

Tx: immunoglobulin replacement.

Question 15

Congenital lymphedema

Answer 15

Lymphatic network dysgenesis occurs in Turner Syndrome

Question 16

NF1

Answer 16

NF1 suppressor gene mutation on chromosome 17, encodes neurofibromin.

Cafe au lait spots, freckling, multiple neurofibromas, Lisch nodules. Can have low-grade optic pathway glioma.

Question 17

NF2

Answer 17

NF2 suppressor gene on chromosome 22, encodes merlin.

Bilateral acoustic neuromas.

Question 18

Genes/Conditions related to Pheochromocytoma

Answer 18

NF1 - Neurofibromatosis
RET - MEN2 (Parathyroid, pheo, medullary thyroid)
VHL - von Hippel Lindau

Question 19

Li-fraumeni syndrome

Answer 19

P53 mutation

sarcomas. breast cancer, adrenal carcinoma, gliomas, medulloblastomas

Question 20

Chronic granulomatous disease

Answer 20

X linked most of the time
recurrent infections with catalase positive organisms (S. aureus, serratia, aspergillus)
Decreased NADPH oxide activty

Question 21

X linked agammaglobulinemia

Answer 21

Decreased IgG, recurrent sinupulmonary infections and bacteremia.

Question 22

Leukocyte adhesion deficiency

Answer 22

Decreased neutrophil chemotaxis, recurrent infections with S. aureus and other skin flora but the infection sites often have minimal pus.

Question 23

Hyper IgE Syndrome (Job Syndrome)

Answer 23

Recurrent abscesses and pulmonary infections. Broad nose and scoliosis. Autosomal dominant.

Question 24

Fanconi Anemia

Answer 24

DNA repair defect

Short stature, hypoplastic thumbs, hypo/hyperpigmented macules, genitourinary malformations

Pancytopenia, positive chromosomal breakage

Tx: stem cell transplant

Question 25

Selective IgA deficiency

Answer 25

Most common primary immunodeficiency recurrent sinopulmonary and GI infections associated with asthma, eczema, celiac Anaphylaxis to blood transfusions (antibodies to IgA)

Question 26

Neonatal polycythemia

Answer 26

HCT >65% Intrauterine hypoxia or increased blood transfusion Resp distress IV fluids + glucose

Question 27

Landau-Kleffner syndrome

Answer 27

Regression of language skills due to severe epilepsy

Question 28

Tuberous sclerosis

Answer 28

Seizures, cognitive defects, autistic features with skin findings such as hypopigmented macules, angiofibromas, and forehead plaques.

Question 29

Rett Syndrome

Answer 29

Neurodevelopment disorder occuring mainly in girls. Normal development and then regression of speech, loss of purposeful hand movements, gait abnormalities, and seizures.

Question 30

Lesch-Nyhan Syndrome

Answer 30

Hypoxanthine and uric acid accumulation Infants exhibit hypotonia and delayed milestones Eventually, become hypertonic and exhibit self-mutilating behavior

Question 31

Alport Syndrome

Answer 31

``` Collagen IV mutation Cant see cant pee cant hear a bee Starts with isolated hematuria, then sensorineural hearing loss, and vision loss. Longitudinal splitting of GBM X linked mostly ```

Question 32

Wiskott-Aldrich Syndrome

Answer 32

Impaired cytoskeleton changes in leukocytes and platelets. Eczema, Microthrombocytopenia, recurrent infection. Xlinked Stem cell transplant

Question 33

Hereditary Hemochromatosis

Answer 33

Hyperpigmentation, arthralgia, chondrocalcinosis, elevated liver enzymes that progress into cirrhosis, DM2, hypogonadism, hypothyroid, cardiomyopathy, increased susceptibility to Listeria, Vibrio, and Yersinia.