TYPE-I BIPOLAR DISORDER ASSOCIATED WITH A FRAGILE SITE ON CHROMOSOME-1

The objective of this paper is to study the association between chromo somal fragile sites and type I bipolar disorder, This case-control stu dy compares bipolar patients with normal controls, Ten cases of type I bipolar disorder diagnosed according to DSM-III-R criteria and the Co mposite International Diagnostic Interview (CIDI) were selected from t he Escola Paulista affective disorders outpatient clinic and 10 health y controls (CIDI negative for psychiatric diagnoses) matched for sex a nd age were drawn from the otorhinolaryngologic outpatient clinic of t he same hospital, The cytogenetic analysis was carried out with blood lymphocytes, which were cultured in a folic acid-free medium. A total of 100 mitoses per subject were blindly analyzed to the psychiatric di agnostic assignment, and fragile sites were identified according to a minimum expected frequency of events per band in conformity with a Poi sson distribution. A higher frequency of chromosomal lesions for cases than controls was found for the following bands: 1q32, 5q31, and 11q2 3, the 1q32 being considered a fragile site. Although no evident neuro psychiatric etiological component has been mapped to the 1q32 region s o far, this finding may lead to further investigation of a possible li nkage between genetic markers of this region and bipolar disorder, (C) 1995 Wiley-Liss, Inc.