Table 1.

Genetic model-fitting results: variance components (with 95% CI)

Genetic model	Twins included	Modelled as next dizygotic pair concordant	Additive genetic component (A)	Common environmental (C) or dominant genetic (D) component	Unique environmental component (E)
ADE	All	No	0.00 (0.00 to 0.80)	0.73 (0.00 to 0.85)	0.27 (0.15 to 0.45)
AE	All	No	0.71 (0.53 to 0.84)	–	0.29 (0.16 to 0.47)
ACE	All	Yes	0.52 (0.04 to 0.85)	0.21 (0.00 to 0.58)	0.27 (0.15 to 0.45)
AE	All	Yes	0.76 (0.60 to 0.86)	–	0.24 (0.14 to 0.40)
ADE	Sporadic	No	0.00 (0.00 to 0.75)	0.64 (0.00 to 0.81)	0.36 (0.19 to 0.59)
AE	Sporadic	No	0.61 (0.38 to 0.78)	–	0.39 (0.22 to 0.62)
ACE	Sporadic	Yes	0.36 (0.00 to 0.80)	0.30 (0.00 to 0.63)	0.35 (0.19 to 0.57)
AE	Sporadic	Yes	0.70 (0.52 to 0.83)	–	0.30 (0.17 to 0.48)