Childhood-onset schizophrenia: smooth pursuit eye-tracking dysfunction in family members.
BACKGROUND
Childhood-onset schizophrenia (COS), a severe form of the disorder, is of interest for etiologic studies. Smooth pursuit eye-tracking dysfunction (ETD) is a biological marker for schizophrenia.


OBJECTIVE
To compare familial eye-tracking abnormalities for COS and adult-onset schizophrenia (AOS).


METHODS
Eye-tracking performance for 70 COS parents, 64 AOS parents and 20 COS siblings was compared to their respective age-matched control groups.


RESULTS
COS and AOS parents had higher rate of dichotomously rated eye-tracking dysfunction than their respective controls (16% vs. 1% and 22% vs. 4%, respectively). COS parents and siblings also differed from controls on several continuous measures. However, scores for COS, AOS and control groups overlapped extensively.


CONCLUSIONS
Genetic factors underlying eye-tracking dysfunction appear more salient for COS. However, eye-tracking measures have to be used with caution for endophenotypic definition due to low predictive power.


BACKGROUND
The study was done at the National Institutes of Health.
Sporn
Alexandra
A
Child Psychiatry Branch, National Institute of Mental Health, National Institute of Health, Bldg 10, Rm 3N202, Bethesda, MD 20892, USA. sporna@intra.nimh.nih.gov
Greenstein
Deanna
D
Gogtay
Nitin
N
Sailer
Franziska
F
Hommer
Daniel W
DW
Rawlings
Robert
R
Nicolson
Rob
R
Egan
Michael F
MF
Lenane
Marge
M
Gochman
Peter
P
Weinberger
Daniel R
DR
Rapoport
Judith L
JL
D000328:Adult; D000367:Age Factors; D002648:Child; D005260:Female; D006304:Health Status; D006801:Humans; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D015835:Ocular Motility Disorders / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology*; D012438:Saccades / Q000502:physiology*; D012559:Schizophrenia / Q000150:complications / Q000235:genetics / Q000503:physiopathology; D012561:Schizophrenia, Childhood / Q000150:complications / Q000235:genetics* / Q000503:physiopathology*; D012720:Severity of Illness Index