Table 1.

The clinical characteristics of the study sample

	D85D major homozygotes	D85N heterozygotes	N85N minor homozygotes
All subjects
n (%)	689 (96.8)	21 (2.9)	2 (0.3)
Age (years)	29.7 ± 20.0	28.7 ± 20.2	7.0 ± 4.2
Males (%)	280 (40.6)	8 (38.1)	2 (100)
QTc (ms)	458 ± 36.8	472 ± 35.2	468 ± 34.6
Founder mutation status
KCNQ1 G589D
n	474a	16b	2
QTc	459 ± 36.2	479 ± 31.0	468 ± 34.6
KCNQ1 IVS7-2A>G
n	66b	0	0
QTc	465 ± 30.0	-	-
KCNH2 L552S
n	71c	2	0
QTc	464 ± 48.3	490 ± 7.1	-
KCNH2 R176W
n	84d	4e	0
QTc	445 ± 30.6	442 ± 46.5	-

The figures represent the mean ± SD. SD, standard deviation; QTc, heart rate-corrected QT interval.

^aFour subjects carrying also KCNH2 R176W, one KCNH2 L552S, and one KCNQ1 Y171X.

^bOne subject carrying also KCNH2 R176W.

^cIncludes two KCNH2 L552S homozygotes and one subject carrying also KCNQ1 G589D.

^dFour subjects carrying also KCNQ1 G589D and one KCNQ1 IVS7-2A>G.

^eOne subject carrying also KCNQ1 G589D.