Repeat length variation in the dopamine D4 receptor gene shows no evidence of association with schizophrenia.
The D4 receptor has been shown to exist in several allelic forms (Van Tol et al., Nature 358:149-152, 1992) reflecting variation in the number of 48 base-pair sequence repeats in the putative cytoplasmic loop. We report a comparison of repeat length variation between schizophrenic patients and controls. Our sample of 106 unrelated schizophrenic cases and 119 controls showed no significant differences in allele or genotype distribution between patients and controls. In particular, we were unable to support the previous observation of an excess of 4-repeat homozygotes in patients.
Daniels
J
J
Department of Psychological Medicine, University of Wales College of Medicine, Cardiff, United Kingdom.
Williams
J
J
Mant
R
R
Asherson
P
P
McGuffin
P
P
Owen
M J
MJ
D000483:Alleles; D001483:Base Sequence; D004247:DNA / Q000032:analysis; D014644:Genetic Variation; D005838:Genotype; D006801:Humans; D008969:Molecular Sequence Data; D011954:Receptors, Dopamine / Q000235:genetics*; D017448:Receptors, Dopamine D2; D050638:Receptors, Dopamine D4; D012091:Repetitive Sequences, Nucleic Acid; D012559:Schizophrenia / Q000235:genetics*
C493599:DRD4 protein, human; D011954:Receptors, Dopamine; D017448:Receptors, Dopamine D2; D050638:Receptors, Dopamine D4; D004247:DNA