Table 3. Number of new and expected cases.

Age, y	1 st-degree relative, n	Dilated aorta, n	2nd-degree relative, n	Dilated aorta, n	Dilated aorta, total n
18–30	10	0	18	1	1
30–39	10	1	19	3	4
40–49	13	6	11	0	6
50–59	11	5	1	0	5
60–69	10	3	1	0	3
70+	2	0	0	0	0
Total (expected)	56	15 (28)	50	4 (12.5)	19 (40.5)

The majority of individuals with dilatation of the aorta were found among first-degree relatives. The number of new cases (19) was significantly lower than would be expected for dominant inheritance (40).