Lecture 3

Question 1

Neurofibromatosis I leads to exceedingly pleotropic phenotypic changes due to the large differentiation in the ________ of NF1 mutations.

Answer 1

expressivity

Question 2

Cafe au lai spots is classic for what genetic disorder?

Answer 2

neurofibromatosis I

Question 3

What is the primary intervention for managing neurofibromatosis I?

Answer 3

symptom mitigation

Question 4

Familial adenomatous polyposis is a mutation in what gene?

Answer 4

APC gene

Question 5

what is the diagnostic criteria for familial adenomatous polyposis?

Answer 5

• > 100 colorectal polyps

- >10 colorectal polyps in an individual with a known affected family member

Question 6

Patients at-risk for familial adenomatous polyposis need to begin yearly screening with colonoscopy at what age?

Answer 6

10-12 years of age onward

Question 7

In hereditary nonpolyposis colon cancer in what part of the colon are tumors commonly found?

Answer 7

• ascending and transverse colon

Question 8

What are the 2 management options for hereditary nonpolyposis colon cancer?

Answer 8

• surveillance colonoscopy starting at age 25

- prophylactic colectomy at age 25

Question 9

Marfan disease results from a mutation in what gene?

Answer 9

fibrillin 1

Question 10

What is the main cardiovascular phenotypic manifestation of Marfan disease?

Answer 10

aortic dilatation leading to dissection

Question 11

Why is it important to ask men about their family history for female breast cancer?

Answer 11

• BRCA 1/2 is associated with prostate cancer

Question 12

What is a therapeutic intervention for hereditary breast and ovarian cancer?

Answer 12

• bilateral prophylactic mastectomy and salpingoophorectomy

Question 13

What are the 3 most common manifestation of MEN-1?

Answer 13

• hyperparathyroidism (most common)
• pancreatic tumors
• anterior pituitary adenomas

Question 14

How is MEN-1 diagnosed and treated?

Answer 14

• diagnosed with DNA analysis

- treat each tumor on a case-by-case basis

Question 15

hereditary hemochromatosis is a disorder of ______ overload

Answer 15

iron

Question 16

hereditary hemochromatosis is caused by a mutation in what gene?

Answer 16

HFE gene

Question 17

Why are women with hereditary hemochromatosis generally asymptomatic?

Answer 17

they loss iron through menstruation

Question 18

What is the treatment for hereditary hemochromatosis and at what ferritin level should you begin?

Answer 18

• treatment is phlebotomy

- start when ferritin level > 50 mg/mL

Question 19

cystic fibrosis primarily affects these 3 organs.

Answer 19

• lung
• pancreas
• GI tract

Question 20

What is the sign for cystic fibrosis in neonatals?

Answer 20

• meconium ileus

Question 21

cystic fibrosis leads to hypertrophy of what heart chamber?

Answer 21

right ventricular hypertrophy

Question 22

How is cystic fibrosis diagnosed?

Answer 22

clinical symptoms and chloride sweat test

Question 23

What is the natural history of phenylketonuria (PKU)?

Answer 23

• patient will present normal at birth and as dietary phenylalanine builds up their mental capacity will deteriorate

Question 24

What is the management for PKU?

Answer 24

• neonatal screening

- if positive, initiate a phenylalanine restricted diet

Question 25

syndromic hereditary deafness is caused by a mutation in what gene?

Answer 25

GJB2 gene mutations

Question 26

What is the difference in the natural history of hereditary deafness if it is due to an autosomal dominant vs. recessive pattern?

Answer 26

- recessive results in neonatal onset deafness | - dominant results in progressive deafness of childhood

Question 27

For patients who present with hereditary deafness at birth what is a promising treatment option if it is performed before 3 years of age?

Answer 27

cochlear implants

Question 28

What is the phenotypic manifestation of ADPKD?

Answer 28

- mass effect on the kidneys d/t cyst obstruction that appears in the 3rd or 4th decade of life

Question 29

What sign usually precedes other symptoms of ADPKD?

Answer 29

hypertension

Question 30

What is the treatment of ADPKD?

Answer 30

- aggressive tx of hypertension - treatment of UTIs - if needed, drainage and chemical sclerosis of the cysts

Question 31

The gower maneuver when going from sitting to standing is a common sign of what x-linked disorder?

Answer 31

duchenne muscular dystrophy

Question 32

full mutation stage of fragile X syndrome occurs when you get >______ CGG repeats.

Answer 32

>200 repeats

Question 33

Decreases growth and head circumference trajectory, rapid loss of speaking ability, and loss of purposeful hand movements are manifestations of what x-linked disorder?

Answer 33

Rett Syndrome

Question 34

What does MELAS stand for?

Answer 34

- mitochondrial myopathy - encephalopathy - lactic acidosis - strokelike episodes

Question 35

MELAS is the most common _________.

Answer 35

mitochondrial encephalomyopathy

Question 36

What is the first sign of MELAS syndrome?

Answer 36

seizures

Question 37

Stroke-like presentation in someone younger than 40 without demonstrable stroke on CT scan should make you consider this diagnosis.

Answer 37

MELAS syndrome

Question 38

What 3 gene loci have been identified as causative for Alzheimer's?

Answer 38

- beta-amyloid protein gene, APP - presenilin 1 gene (PSEN1) - presenilin 2 gene (PSEN2)

Question 39

Late onset Alzheimer's disease is associated with what type of inheritance?

Answer 39

multifactorial inheritance