Table 1.

Sample Description

	Nuclear Familiesa	Extended Pedigreesb
Family information
Number of families	296	296
Average size	4.6	11.2
Average generations	2.0	2.7
Relative pairs
Sibling	714	4113
Half-sibling	17	40
Parent-child	1530	4644
Grandparent-grandchild	18	2368
Avuncular	8	3294
Cousin	0	235
Subjects
Total subjects	1366	3304
Males/females	736/630	1508/1795
SZ	321	391
BPD	25	60
MDD	201	296
Other disorder	2	53
Never mentally ill	748	2449
Unknown diagnosis	69	49
Relative frequency
SZ	24.8%	12.0%
SZ + BPD	26.7%	13.9%
SZ + BPD + MDD	42.2%	23.0%

Note: BPD, bipolar disorder; MDD, major depressive disorder; SZ, schizophrenia.

^aNuclear families include 1297 subjects directly diagnosed via the Diagnostic Interview for Genetic Studies, as well as 1337 subjects that provided Family Interview for Genetic Studies information for all included family members and additional nonparticipating subjects.

^bExtended pedigrees include additional subjects indirectly diagnosed via the Family Interview for Genetic Studies information obtained from directly assessed first-degree relatives.