CV Genetics Flashcards Preview

Cardiovascular > CV Genetics > Flashcards

Flashcards in CV Genetics Deck (29):
1

What is pleitropy?

When one genetic mutation effects multiple traits/phenotypes

2

What is genetic heterogeniety?

When one disease can be caused by multiple genetic mutations

3

Wht is variable expressivity?

Individuals have variable expression of diseases

4

What is RWS?

A genetic disorder that causes LQTS w/ no deafness

AD; 50% penetrance, genetic heterogeniety (10 genes)

5

Most common RWS mutation

KCNQ1 >60% of cases; has highest incidence of cardiac events

6

Which RWS mutation has symptoms triggered by sleep?

SCN5A; Na channel mutation

7

RWS Treatment

Beta-blockers
Pacemakers
ICD

8

Jervel and Lange-Nielson Syndrome

AR; congenital LQTS w/ bilateral sensorineural deafness

9

Jervell and Lange-Nielson Syndrome mutations

KCNQ1 = 90% (LQTS type 1)
KCNE1 = 10% (LQTS type 5)

10

Jervell and Lange-Nielson Syndrome mortality/complications

-Increased risk of SIDS
->50% of untreated die before 15 years old

11

Current LQTS genetic testing detection rate

75%; 25% of LQTS do not have a detectable gene mutation

12

Does a negative genetic test rule out LQTS?

No

13

What is Brugada syndrome

Disorder characterized by ST-segment elevation in leads V1-V3

Syncope, SIDS, SUNDS

14

Major genetic mutation in Brugada

SCN5A gene; alpha subunit of Na channel

15

What is catecholaminergic polymorphic ventricular tachycardia (CPVT)

Bidirectional polymorphic ventricular tachycardia, can become VFib

-Exercise or emotional trigger causes syncope

16

CPVT mutation

RYR2 (ryanodine receptor channel) = AD inheritance

CASQ2 (calsequesterin of SR) = AR inheritance

17

HCM inheritance

AD inheritance
-50-60% with a famhx have sarcomere gene mutation
-20-30% without a famhx have a sarcomere gene mutation

18

HCM mutated genes

MYH17 - myosin head; classic

MYBPC3; later age of onset

TNNT2; mild or absent LVH, higher risk of arrhythmias and SCD

19

What two diseases resemble HCM

Danon disease

Fabry disease

20

Which HCM mutation has highest risk of arrhythmias

TNNT2

21

What is the primary indication of cardiac transplantation

DCM

22

What is idiopathic DCM

All acquired causes excluded, except genetic causes

23

DCM detection rate

30%; high genetic heterogeneity; 20 genes, most are AD

24

LMNA mutation

DCM; prominent conduction disease

Pleiotrophic gene; involved in other diseases

25

When is screening recommended for cardiomyopathy

-Asymptomatic first degree relatives
-Relatives known to carry the mutations

26

HCM screening

Positive or negative:
-yearly during puberty
-Every 3 years until 30
-Every 5 years after 30 (if negative, only when symptomatic)

27

DCM screening

Positive mutation:
-yearly during childhood
-every 1-3 years during adulthood

Negative mutation:
-every 3-5 years

28

Familial hypercholesterolemia levels

Untreated adults:
-LDL > 190 mg/dL or TC > 310

Untreated children:
-LDL >160, TC >230

Homozygous mutation:
TC > 500

29

Familial hypercholesterolemia mutations

LDL-R = most common
ApoB
PCSK9 = least common

HeFH = AD
HoFH = AR