Association between the DTNBP1 gene and intelligence: a case-control study in young patients with schizophrenia and related disorders and unaffected siblings

Table 4 Overview of subjects' countries of origin

	Subject
Country of origin	Patients	Siblings	Controls
Netherlands (white Caucasian)	48	25	22
Turkey	3	1	0
Morocco	4	0	4
Surinam or Dutch Antilles	17	3	5
Missing	4	2	0

Country of origin did not differ significantly between subject groups (Fisher's Exact = 9.44, p = 0.24).