1Dig. Dis. Sci. 2006 Sep 51: 1567-70
TitlePeutz-Jeghers syndrome diagnosed in a schizophrenic patient with a large deletion in the STK11 gene.
SCZ Keywordsschizophrenia, schizophrenic
2PLoS ONE 2007 -1 2: e895
TitleDNA methylation in the human cerebral cortex is dynamically regulated throughout the life span and involves differentiated neurons.
AbstractThe role of DNA cytosine methylation, an epigenetic regulator of chromatin structure and function, during normal and pathological brain development and aging remains unclear. Here, we examined by MethyLight PCR the DNA methylation status at 50 loci, encompassing primarily 5' CpG islands of genes related to CNS growth and development, in temporal neocortex of 125 subjects ranging in age from 17 weeks of gestation to 104 years old. Two psychiatric disease cohorts--defined by chronic neurodegeneration (Alzheimer's) or lack thereof (schizophrenia)--were included. A robust and progressive rise in DNA methylation levels across the lifespan was observed for 8/50 loci (GABRA2, GAD1, HOXA1, NEUROD1, NEUROD2, PGR, STK11, SYK) typically in conjunction with declining levels of the corresponding mRNAs. Another 16 loci were defined by a sharp rise in DNA methylation levels within the first few months or years after birth. Disease-associated changes were limited to 2/50 loci in the Alzheimer's cohort, which appeared to reflect an acceleration of the age-related change in normal brain. Additionally, methylation studies on sorted nuclei provided evidence for bidirectional methylation events in cortical neurons during the transition from childhood to advanced age, as reflected by significant increases at 3, and a decrease at 1 of 10 loci. Furthermore, the DNMT3a de novo DNA methyl-transferase was expressed across all ages, including a subset of neurons residing in layers III and V of the mature cortex. Therefore, DNA methylation is dynamically regulated in the human cerebral cortex throughout the lifespan, involves differentiated neurons, and affects a substantial portion of genes predominantly by an age-related increase.
SCZ Keywordsschizophrenia, schizophrenic
3J. Biomed. Sci. 2010 -1 17: 2
TitleGenetic copy number variants in sib pairs both affected with schizophrenia.
Abstractschizophrenia is a complex disorder with involvement of multiple genes.
In this study, genome-wide screening for DNA copy-number variations (CNVs) was conducted for ten pairs, a total of 20 cases, of affected siblings using oligonucleotide array-based CGH.
We found negative symptoms were significantly more severe (p < 0.05) in the subgroup that harbored more genetic imbalance (n >== 13, n = number of CNV-disrupted genes) as compared with the subgroup with fewer CNVs (n <== 6), indicating that the degree of genetic imbalance may influence the severity of the negative symptoms of schizophrenia. Four central nervous system (CNS) related genes including CCAAT/enhancer binding protein, delta (CEBPD, 8q11.21), retinoid x receptor, alpha (RXRA, 9q34.2), LIM homeobox protein 5 (LHX5, 12q24.13) and serine/threonine kinase 11 (STK11, 19p13.3) are recurrently (incidence >== 16.7%) disrupted by CNVs. Two genes, PVR (poliovirus receptor) and BU678720, are concordantly deleted in one and two, respectively, pairs of co-affected siblings. However, we did not find a significant association of this BU678720 deletion and schizophrenia in a large case-control sample.
We conclude that the high genetic loading of CNVs may be the underlying cause of negative symptoms of schizophrenia, and the CNS-related genes revealed by this study warrant further investigation.
SCZ Keywordsschizophrenia, schizophrenic