Table :
TABLE
12.7
• Degree of Relatedness and Risk of Developing Schizophrenia
Family member(s) with schizophrenia
Risk of developing schizophrenia
First cousin
2%
Half-sibling
6%
Full sibling
9%
One parent
13%
Two parents
46%
Fraternal twin
14–17%
Identical twin
46–53%
Sources: Gottesman, 1991; Kendler, 1983.