Schizophrenia is a severe psychiatric disorder with high heritability. Consortia efforts and technological advancements have led to a substantial increase in knowledge of the genetic architecture of schizophrenia over the past decade. In this article, we provide an overview of the current understanding of the genetics of schizophrenia, outline remaining challenges, and summarise future directions of research. World-wide collaborations have resulted in genome-wide association studies (GWAS) in over 56 000 schizophrenia cases and 78 000 controls, which identified 176 distinct genetic loci. The latest GWAS from the Psychiatric Genetics Consortium, available as a pre-print, indicates that 270 distinct common genetic loci have now been associated with schizophrenia. Polygenic risk scores can currently explain around 7.7% of the variance in schizophrenia case-control status. Rare variant studies have implicated eight rare copy-number variants, and an increased burden of loss-of-function variants in SETD1A, as increasing the risk of schizophrenia. The latest exome sequencing study, available as a pre-print, implicates a burden of rare coding variants in a further nine genes. Gene-set analyses have demonstrated significant enrichment of both common and rare genetic variants associated with schizophrenia in synaptic pathways. To address current challenges, future genetic studies of schizophrenia need increased sample sizes from more diverse populations. Continued expansion of international collaboration will likely identify new genetic regions, improve fine-mapping to identify causal variants, and increase our understanding of the biology and mechanisms of schizophrenia.

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In this study vegetation composition of understorey species of Malam Jabba forest is evaluated by multivariate analysis. Thirteen stands were quantitatively sampled by point centered quarter method. Environmental variables were recorded and correlate them with vegetation characteristic. In 13 stands 49 understory species were recorded. Multivariate techniques were employed to assess the vegetation groups and underlying group structure. Agglomerative Cluster analysis (Ward’s method) discloses four main groups of vegetation while Principle Component Analysis (PCA) clearly ordinate these groups on all three axes. The most common species distributed in all four groups were Adiantum capillus veneris, Adiantum venestum, Berberis lyceum, Chrysopogon aucheri, Oxalis corniculata, Pteris cretica and Trifolium repens while these species were observed in three groups i.e.  Punica granatum and Plantago amplexicaulis. The Group 1 comprises on 23 species and the dominant species were Androsace rotundifolia, Aristida cynantha, Berberis lyceum, Dryopteris filix, Oxalis corniculata, Pteris cretica and Trifolium repens while Group 2 comprises on 18 species, the dominant were Pteris cretica, Adiantum venestum, Duchesnea indica while some other species included, Berberis lyceum, Chrysopogon aucheri, Chrysopogon aucheri, Dryopteris juxtapostia and Morus alba. Group 3 & 4 comprises 31 species each, in which 18 species were common i.e. Adiantum capillus veneris, Adiantum venustum, Arisaema jacquemontii,  Berberis lyceum, Chrysopogon aucheri,  Dryopteris filix, Dryopteris juxtapostia, Duchesnea indica, Oxalis corniculata, Plantago amplexicaulis, Polygala erioptera,  Prunus avium, Pteris cretica, Punica granatum, Ranunculus muricatus, Rosa macrophylla, Trifolium fragiferum and Trifolium repens.  Among the environmental variables elevation and slope played an overriding role in the distribution of vegetation. The relationships between the six PCA ordination axes with environmental factors generally showed few significant relations, only axis 2 showed marked relationship with all edaphic variables (except pH), suggesting that the edaphic gradient has an overriding role in the composition and distribution of understorey vegetation.  Some other environmental factors showed weak correlations with ordination axes, it could be spurious correlation. Malam Jabba forests are highly disturbed due to civil war and anthropogenic causes. Slope of the forests prove to be an overriding role in the distribution of vegetation as evaluated by analysis of variance.

IntroductionIndividuals with schizophrenia are at a high risk of physical health comorbidities and premature mortality. Cardiovascular and metabolic causes are an important contributor. There are gaps in monitoring, documenting and managing these physical health comorbidities. Because of their condition, patients themselves may not be aware of these comorbidities and may not be able to follow a lifestyle that prevents and manages the complications. In many low-income and middle-income countries including Pakistan, the bulk of the burden of care for those struggling with schizophrenia falls on the families.ObjectivesTo determine the rate of self-reported physical health disorders and risk factors, like body mass index (BMI) and smoking, associated with cardiovascular and metabolic disorders in cases of schizophrenia compared with a group of mentally healthy controls.DesignA case-controlled, cross-sectional multicentre study of patients with schizophrenia in Pakistan.SettingsMultiple data collection sites across the country for patients, that is, public and private psychiatric OPDs (out patient departments), specialised psychiatric care facilities, and psychiatric wards of teaching and district level hospitals. Healthy controls were enrolled from the community.ParticipantsWe report a total of 6838 participants’ data with (N 3411 (49.9%)) cases of schizophrenia compared with a group of healthy controls (N 3427 (50.1%)).ResultsBMI (OR 0.98 (CI 0.97 to 0.99), p=0.0025), and the rate of smoking is higher in patients with schizophrenia than in controls. Problems with vision (OR 0.13 (0.08 to 0.2), joint pain (OR 0.18 (0.07 to 0.44)) and high cholesterol (OR 0.13 (0.05 to 0.35)) have higher reported prevalence in controls. The cases describe more physical health disorders in the category ‘other’ (OR 4.65 (3.01 to 7.18)). This captures residual disorders not listed in the questionnaire.ConclusionsParticipants with schizophrenia in comparison with controls report more disorders. The access in the ‘other’ category may be a reflection of undiagnosed disorders.