1Hum. Hered. 2006 -1 62: 47-54
PMID17019084
TitleA posterior probability of linkage-based re-analysis of schizophrenia data yields evidence of linkage to chromosomes 1 and 17.
AbstractLinkage analysis using 22 Canadian pedigrees identified a promising schizophrenia candidate region on 1q23 with a maximum 2-point HLOD under a recessive model of 5.8 [Brzustowicz et al. 2000]. In the current study, we revisited this data set using a Bayesian linkage analysis technique, namely the posterior probability of linkage (PPL).
The PPL has been developed as an alternative to traditional linkage analysis. It differs from both LOD scores and 'non-parametric' methods in that it directly measures the probability of linkage given the data, and incorporates prior genomic information.
As expected, PPL results for 1q23 supported the previously observed linkage, with an estimated multipoint PPL of 99.7%. However, the PPL supported two further results: a second peak on chromosome 1 at 1p13 with a multipoint with PPL of 70% and a chromosome 17 marker (D17S784 at 17q25) with a multipoint PPL of 44%.
The PPL-based analysis presented has the advantage over other likelihood-based linkage methods in that it avoids maximization and produces a less complex view of the strength of evidence for linkage.
SCZ Keywordsschizophrenia, schizophrenics
2Am J Psychiatry 2014 Mar 171: 350-9
PMID24170318
TitleRevisiting schizophrenia linkage data in the NIMH Repository: reanalysis of regularized data across multiple studies.
AbstractThe Combined Analysis of Psychiatric Studies (CAPS) project conducted extensive review and regularization across studies of all schizophrenia linkage data available as of 2011 from the National Institute of Mental Health-funded Center for Collaborative Genomic Studies on Mental Disorders, also known as the Human Genetics Initiative (HGI). The authors reanalyzed the data using statistical methods tailored to accumulation of evidence across multiple, potentially highly heterogeneous, sets of data.
Data were subdivided based on contributing study, major population group, and presence or absence within families of schizophrenia with a substantial affective component. The posterior probability of linkage (PPL) statistical framework was used to sequentially update linkage evidence across these data subsets (omnibus results).
While some loci previously implicated using the HGI data were also identified in the present omnibus analysis (2q36.1, 15q23), others were not. Several loci were found that had not previously been reported in the HGI samples but are supported by independent linkage or association studies (3q28, 12q23.1, 11p11.2, Xq26.1). Not surprisingly, differences were seen across population groups. Of particular interest are signals on 11p15.3, 11p11.2, and Xq26.1, for which data from families with a substantial affective component support linkage while data from the remaining families provide evidence against linkage. All three of these loci overlap with loci reported in independent studies of bipolar disorder or mixed bipolar-schizophrenia samples.
Public data repositories provide the opportunity to leverage large multisite data sets for studying complex disorders. Analysis with a statistical method specifically designed for such data enables us to extract new information from an existing data resource.
SCZ Keywordsschizophrenia, schizophrenics
3Zhonghua Yi Xue Za Zhi 2015 Mar 95: 823-6
PMID26080913
Title[Prepulse inhibition of startle reflex in schizophrenics and healthy adults].
AbstractTo evaluate the characteristics of sensory gating inhibition and variation of schizophrenia with both prepulse inhibition (PPI) and P50.
The PPI of startle reflex and P50 were tested by an event-related potential (ERP) recorder in 82 first episode schizophrenics (FES) recruited from September 2007 to February 2014 at Shanghai Mental Health Hospital and 78 healthy controls (NC) from hospital staffs and local residents for the same period. All patients fulfilled the evaluation of PPI with strong stimulus alone and strong + weak stimulus paradigm, P50 with conditioning (S1)-testing (S2) paradigm. The psychotic symptoms were assessed with Positive and Negative Syndrome Scale (PANSS).
(1) Compared with control group, schizophrenia group had increased P(L) (NC: (89 ▒ 14) ms, FES: (97 ▒ 17) ms, P < 0.05) and PPL, decreased amplitude (NC: (92 ▒ 21) ms, (24 ▒ 14) ÁV, FSZ: (96 ▒ 20) ms, (41 ▒ 29) ÁV, P < 0.05, 0.01), lower PPI inhibition ratio (NC: (67 ▒ 32)%, FSZ: (41 ▒ 37)%, P < 0.05). (2) Compared with NC group, there were increased S2 amplitude [NC: (3 ▒ 2) ÁV vs FES: (5 ▒ 3) ÁV, P < 0.05] and ratio of S2/S1 amplitude [(43 ▒ 22) % vs (82 ▒ 41)%, P < 0.05] in schizophrenia group. And P50 inhibition decreased significantly.
schizophrenics have both PPI and P50 impairments. And a combination of PPI inhibition ratio and S2/S1 (P50) may be a better electrocerebrophysiological index for schizophrenia.
SCZ Keywordsschizophrenia, schizophrenics
4Zhonghua Yi Xue Za Zhi 2015 Mar 95: 823-6
PMID26080913
Title[Prepulse inhibition of startle reflex in schizophrenics and healthy adults].
AbstractTo evaluate the characteristics of sensory gating inhibition and variation of schizophrenia with both prepulse inhibition (PPI) and P50.
The PPI of startle reflex and P50 were tested by an event-related potential (ERP) recorder in 82 first episode schizophrenics (FES) recruited from September 2007 to February 2014 at Shanghai Mental Health Hospital and 78 healthy controls (NC) from hospital staffs and local residents for the same period. All patients fulfilled the evaluation of PPI with strong stimulus alone and strong + weak stimulus paradigm, P50 with conditioning (S1)-testing (S2) paradigm. The psychotic symptoms were assessed with Positive and Negative Syndrome Scale (PANSS).
(1) Compared with control group, schizophrenia group had increased P(L) (NC: (89 ▒ 14) ms, FES: (97 ▒ 17) ms, P < 0.05) and PPL, decreased amplitude (NC: (92 ▒ 21) ms, (24 ▒ 14) ÁV, FSZ: (96 ▒ 20) ms, (41 ▒ 29) ÁV, P < 0.05, 0.01), lower PPI inhibition ratio (NC: (67 ▒ 32)%, FSZ: (41 ▒ 37)%, P < 0.05). (2) Compared with NC group, there were increased S2 amplitude [NC: (3 ▒ 2) ÁV vs FES: (5 ▒ 3) ÁV, P < 0.05] and ratio of S2/S1 amplitude [(43 ▒ 22) % vs (82 ▒ 41)%, P < 0.05] in schizophrenia group. And P50 inhibition decreased significantly.
schizophrenics have both PPI and P50 impairments. And a combination of PPI inhibition ratio and S2/S1 (P50) may be a better electrocerebrophysiological index for schizophrenia.
SCZ Keywordsschizophrenia, schizophrenics