TABLE 2.

Maximum credible population frequencies and maximum tolerated ExAC allele counts for variants causative of exemplar inherited cardiac conditions, assuming a penetrance of 0.5 throughout.

Disease	Maximum allelic contribution	Prevalence	Penetrance*	Maximum population frequency	Maximum tolerated ExAC allele count
Marfan	0.015	1/3000	0.5	5.0x10-6	2
Noonan	0.10	1/1000	0.5	1.0x10-4	18
CPVT	0.10	1/10,000	0.5	1.0x10-5	3
Classic Ehlers-Danlos	0.40	1/20,000	0.5	2.0x10-5	5

CPVT - catecholaminergic polymorphic ventricular tachycardia; FH - familial hypercholesterolaemia. Prevalence estimates (taken as the highest value reported) were obtained from: Marfan³², Noonan¹⁸, CPVT¹⁹ and classical Ehlers-Danlos²⁰.