Correction: Exome sequencing of Pakistani consanguineous families identifies 30 novel candidate genes for recessive intellectual disability.

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Exome sequencing of Pakistani consanguineous families identifies 30 novel candidate genes for recessive intellectual disability.

Intellectual disability (ID) is a clinically and genetically heterogeneous disorder, affecting 1-3% of the general population. Although research into the genetic causes of ID has recently gained momentum, identification of pathogenic mutations that cause autosomal recessive ID (ARID) has lagged behind, predominantly due to non-availability of sizeable families. Here we present the results of exome sequencing in 121 large consanguineous Pakistani ID families. In 60 families, we identified homozygous or compound heterozygous DNA variants in a single gene, 30 affecting reported ID genes and 30 affecting novel candidate ID genes. Potential pathogenicity of these alleles was supported by co-segregation with the phenotype, low frequency in control populations and the application of stringent bioinformatics analyses. In another eight families segregation of multiple pathogenic variants was observed, affecting 19 genes that were either known or are novel candidates for ID. Transcriptome profiles of normal human brain tissues showed that the novel candidate ID genes formed a network significantly enriched for transcriptional co-expression (P<0.0001) in the frontal cortex during fetal development and in the temporal-parietal and sub-cortex during infancy through adulthood. In addition, proteins encoded by 12 novel ID genes directly interact with previously reported ID proteins in six known pathways essential for cognitive function (P<0.0001). These results suggest that disruptions of temporal parietal and sub-cortical neurogenesis during infancy are critical to the pathophysiology of ID. These findings further expand the existing repertoire of genes involved in ARID, and provide new insights into the molecular mechanisms and the transcriptome map of ID.

Amelioration of ovalbumin induced allergic symptoms in Balb/c mice by potentially probiotic strains of lactobacilli.

To evaluate the antiallergic effect of newly characterised probiotic strains, Lactobacillus fermentum NWS29, Lactobacillus casei NWP08 and Lactobacillus rhamnosus NWP13, mice were divided into six experimental groups: control, ovalbumin (OVA), NWS29, NWP08, NWP13 and L. rhamnosus GG (LGG). Mice were immunised and probiotics were administered via oral gavage followed by challenge with OVA. After last challenge with OVA, inflammatory cells in bronchoalveolar lavage fluid (BALF), recruitment of inflammatory cells in airways and OVA-specific immunoglobulin E (IgE) in serum were determined by Giemsa, haematoxylin and eosin (HE) staining, and ELISA, respectively. Relative mRNA expression of interleukins (IL-4, IL-5, IL-10, IL-13 and IL-17), transforming growth factor-ß (TGF-ß) and interferon-γ (IFN-γ) in lung and spleen tissue was determined by real time RT-PCR. OVA-specific IgE levels, recruitment of eosinophils and mRNA expressions of inflammatory cytokines were remarkably increased in OVA-exposed mice compared with the control group. Administration of NWS29 and NWP13 suppressed inflammatory cell infiltration in airways and BALF, and level of OVA-specific IgE in serum of OVA-exposed mice. Furthermore, NWS29 and NWP13 also abrogated the mRNA expression of 1L-4, IL-5, IL-13 and TGF-ß in mice immunised and exposed to OVA. Our findings suggest that NWS29 and NWP13 might be good candidates for the prevention of allergic airway inflammation.