McQuillan R.,University of Edinburgh |
Eklund N.,Institute for Molecular Medicine Finland FIMM |
Eklund N.,Finnish National Institute for Health and Welfare |
Pirastu N.,University of Trieste |
And 109 more authors.
PLoS Genetics | Year: 2012
Stature is a classical and highly heritable complex trait, with 80%-90% of variation explained by genetic factors. In recent years, genome-wide association studies (GWAS) have successfully identified many common additive variants influencing human height; however, little attention has been given to the potential role of recessive genetic effects. Here, we investigated genome-wide recessive effects by an analysis of inbreeding depression on adult height in over 35,000 people from 21 different population samples. We found a highly significant inverse association between height and genome-wide homozygosity, equivalent to a height reduction of up to 3 cm in the offspring of first cousins compared with the offspring of unrelated individuals, an effect which remained after controlling for the effects of socio-economic status, an important confounder (χ2 = 83.89, df = 1; p = 5.2×10-20). There was, however, a high degree of heterogeneity among populations: whereas the direction of the effect was consistent across most population samples, the effect size differed significantly among populations. It is likely that this reflects true biological heterogeneity: whether or not an effect can be observed will depend on both the variance in homozygosity in the population and the chance inheritance of individual recessive genotypes. These results predict that multiple, rare, recessive variants influence human height. Although this exploratory work focuses on height alone, the methodology developed is generally applicable to heritable quantitative traits (QT), paving the way for an investigation into inbreeding effects, and therefore genetic architecture, on a range of QT of biomedical importance. © 2012 McQuillan et al.
Vozzi D.,Institute for Maternal and Child Health |
Licastro D.,CBM Scrl Genomics |
Martelossi S.,Institute for Maternal and Child Health |
Athanasakis E.,Institute for Maternal and Child Health |
And 2 more authors.
Molecular Syndromology | Year: 2013
Alagille syndrome (ALGS, MIM 118450) is an autosomal dominant, multisystem disorder with high variability. Two genes have been described: JAG1 and NOTCH2. The population prevalence is 1:70,000 based on the presence of neonatal liver disease. The majority of cases (∼97%) are caused by haploinsufficiency of the JAG1 gene on 20p11.2p12, either due to mutations or deletions at the locus. Less than 1% of cases are caused by mutations in NOTCH2. The most widely used methods for mutational screening include denaturing high-performance liquid chromatography (DHPLC) and multiplex ligation-dependent probe amplification (MLPA). Very recently, whole-exome sequencing (WES) has become technically feasible due to the recent advances in next-generation sequencing technologies, therefore offering new opportunities for mutations/genes identification. A proband and its family, negative for the presence of mutations in JAG1 and NOTCH2 genes by neither DHPLC nor MLPA, were analyzed by WES. A missense mutation, not previously described, in JAG1 gene was identified. This result shows an improvement in the mutation detection rate due to novel sequencing technology suggesting the strong need to reanalyze all negative cases. Copyright © 2013 S. Karger AG, Basel.
Yang L.,Harvard University |
Licastro D.,CBM Scrl Genomics |
Cava E.,University of Rome La Sapienza |
Veronese N.,University of Padua |
And 7 more authors.
Cell Reports | Year: 2015
Calorie restriction (CR) retards aging, acts as a hormetic intervention, and increases serum corticosterone and HSP70 expression in rodents. However, less is known regarding the effects of CR on these factors in humans. Serum cortisol and molecular chaperones and autophagic proteins were measured in the skeletal muscle of subjects on CR diets for 3-15 years and in control volunteers. Serum cortisol was higher in the CR group than in age-matched sedentary and endurance athlete groups (15.6 ± 4.6 ng/dl versus 12.3 ± 3.9 ng/dl and 11.2 ± 2.7 ng/dl, respectively; p ≤ 0.001). HSP70, Grp78, beclin-1, and LC3 mRNA and/or protein levels were higher in the skeletal muscle of the CR group compared to controls. Our data indicate that CR in humans is associated with sustained rises in serum cortisol, reduced inflammation, and increases in key molecular chaperones and autophagic mediators involved in cellular protein quality control and removal of dysfunctional proteins and organelles. Yang et al. show that calorie restriction without malnutrition in humans inhibits inflammation, at least in part by elevating serum cortisol concentration, and increases chaperone and autophagy genes and proteins involved in protein quality control and organelle homeostasis in the removal of dysfunctional proteins and organelles from cell. © 2016 The Authors.
Omodei D.,University of Washington |
Licastro D.,CBM Scrl Genomics |
Salvatore F.,CEINGE Biotecnologie Avanzate scarl |
Crosby S.D.,University of Washington |
And 2 more authors.
Aging | Year: 2013
Calorie restriction (CR) without malnutrition is the most robust intervention to slow aging and extend healthy lifespan in experimental model organisms. Several metabolic and molecular adaptations have been hypothesized to play a role in mediating the anti-aging effects of CR, including enhanced stress resistance, reduced oxidative stress and several neuroendocrine modifications. However, little is known about the independent effect of circulating factors in modulating key molecular pathways. In this study, we used sera collected from individuals practicing long-term CR and from age- and sex-matched individuals on a typical US diet to culture human primary fibroblasts and assess the effects on gene expression and stress resistance. We show that treatment of cultured cells with CR sera caused increased expression of stress-response genes and enhanced tolerance to oxidants. Cells cultured in serum from CR individuals showed a 30% increase in resistance to H2O2 damage. Consistently, SOD2 and GPX1 mRNA, two key endogenous antioxidant enzymes, were increased by 2 and 2.5 folds respectively in cells cultured with CR sera. These cellular and molecular adaptations mirror some of the key effects of CR in animals, and further suggest that circulating factors contribute to the CR-mediated protection against oxidative stress and stress-response in humans as well. © Omodei et al.
PubMed | University of Padua, University of Washington, Baylor College of Medicine, University of Verona and 5 more.
Type: Journal Article | Journal: Cell reports | Year: 2016
Calorie restriction (CR) retards aging, acts as a hormetic intervention, and increases serum corticosterone and HSP70 expression in rodents. However, less is known regarding the effects of CR on these factors in humans. Serum cortisol and molecular chaperones and autophagic proteins were measured in the skeletal muscle of subjects on CR diets for 3-15 years and in control volunteers. Serum cortisol was higher in the CR group than in age-matched sedentary and endurance athlete groups (15.6 4.6 ng/dl versus 12.3 3.9 ng/dl and 11.2 2.7 ng/dl, respectively; p 0.001). HSP70, Grp78, beclin-1, and LC3 mRNA and/or protein levels were higher in the skeletal muscle of the CR group compared to controls. Our data indicate that CR in humans is associated with sustained rises in serum cortisol, reduced inflammation, and increases in key molecular chaperones and autophagic mediators involved in cellular protein quality control and removal of dysfunctional proteins and organelles.
Lenzken S.C.,University of Milan Bicocca |
Romeo V.,University of Milan Bicocca |
Zolezzi F.,University of Milan Bicocca |
Cordero F.,University of Turin |
And 13 more authors.
Human Mutation | Year: 2011
Mitochondrial dysfunction has been implicated in the pathogenesis of a number of neurodegenerative disorders including Parkinson, Alzheimer, and Amyotrophic Lateral Sclerosis (ALS). In addition, aberrant mRNA splicing has been documented in neurodegeneration. To characterize the cellular response to mitochondrial perturbations at the level of gene expression and alternative pre-mRNA splicing we used splicing-sensitive microarrays to profile human neuroblastoma SH-SY5Y cells treated with paraquat, a neurotoxic herbicide that induces the formation of reactive oxygen species and causes mitochondrial damage in animal models, and SH-SY5Y cells stably expressing the mutant G93A-SOD1 protein, one of the genetic causes of ALS. In both models we identified a common set of genes whose expression and alternative splicing are deregulated. Pathway analysis of the deregulated genes revealed enrichment in genes involved in neuritogenesis, axon growth and guidance, and synaptogenesis. Alterations in transcription and pre-mRNA splicing of candidate genes were confirmed experimentally in the cell line models as well as in brain and spinal cord of transgenic mice carrying the G93A-SOD1 mutation. Our findings expand the realm of the pathways implicated in neurodegeneration and suggest that alterations of axonal function may descend directly from mitochondrial damage. © 2011 Wiley-Liss, Inc.
Vozzi D.,University of Trieste |
Aaspollu A.,Asper Biotech |
Athanasakis E.,University of Trieste |
Berto A.,University of Ferrara |
And 11 more authors.
Molecular Vision | Year: 2011
Purpose: Usher syndrome is an autosomal recessive disorder characterized by hearing and vision loss. Usher syndrome is divided into three clinical subclasses (type 1, type 2, and type 3), which differ in terms of the severity and progression of hearing loss and the presence or absence of vestibular symptoms. Usher syndrome is defined by significant genetic heterogeneity, with at least 12 distinct loci described and 9 genes identified. This study aims to provide a molecular epidemiology report of Usher syndrome in Italy. Methods: Molecular data have been obtained on 75 unrelated Italian patients using the most up-to date technology available for the screening of Usher syndrome gene mutations, i.e., the genotyping microarray developed by Asper Biotech (Tartu, Estonia), which simultaneously investigates 612 different marker positions using the well established arrayed primer extension methodology (APEX). Results: Using this method, we found that 12% of cases (9 out of 75) harbored homozygous or compound heterozygous mutations in the gene positions analyzed, whereas 20% (15 out of 75) of the patients were characterized by the presence of only one mutated allele based on the positions analyzed. One patient was found to be compound heterozygous for mutations in two different genes and this represents an example of possible digenic inheritance in Usher syndrome. A total of 66.6% of cases (50 out of 75) were found to be completely negative for the presence of Usher syndrome gene mutations in the detected positions. Mutations detected by the array were confirmed by direct sequencing. Conclusions: These findings highlight the efficacy of the APEX-based genotyping approach in the molecular assessment of Usher patients, suggesting the presence of alleles not yet identified and/or the involvement of additional putative genes that may account for the pathogenesis of Usher syndrome. © 2011 Molecular Vision.
Sigalotti L.,Instituto Of Ricovero E Cura A Carattere Scientifico |
Covre A.,Instituto Of Ricovero E Cura A Carattere Scientifico |
Covre A.,University of Siena |
Fratta E.,Instituto Of Ricovero E Cura A Carattere Scientifico |
And 9 more authors.
Journal of Translational Medicine | Year: 2012
Background: The clinical course of cutaneous melanoma (CM) can differ significantly for patients with identical stages of disease, defined clinico-pathologically, and no molecular markers differentiate patients with such a diverse prognosis. This study aimed to define the prognostic value of whole genome DNA methylation profiles in stage III CM.Methods: Genome-wide methylation profiles were evaluated by the Illumina Human Methylation 27 BeadChip assay in short-term neoplastic cell cultures from 45 stage IIIC CM patients. Unsupervised K-means partitioning clustering was exploited to sort patients into 2 groups based on their methylation profiles. Methylation patterns related to the discovered groups were determined using the nearest shrunken centroid classification algorithm. The impact of genome-wide methylation patterns on overall survival (OS) was assessed using Cox regression and Kaplan-Meier analyses.Results: Unsupervised K-means partitioning by whole genome methylation profiles identified classes with significantly different OS in stage IIIC CM patients. Patients with a " favorable" methylation profile had increased OS (P = 0.001, log-rank = 10.2) by Kaplan-Meier analysis. Median OS of stage IIIC patients with a " favorable" vs. " unfavorable" methylation profile were 31.5 and 10.4 months, respectively. The 5 year OS for stage IIIC patients with a " favorable" methylation profile was 41.2% as compared to 0% for patients with an " unfavorable" methylation profile. Among the variables examined by multivariate Cox regression analysis, classification defined by methylation profile was the only predictor of OS (Hazard Ratio = 2.41, for " unfavorable" methylation profile; 95% Confidence Interval: 1.02-5.70; P = 0.045). A 17 gene methylation signature able to correctly assign prognosis (overall error rate = 0) in stage IIIC patients on the basis of distinct methylation-defined groups was also identified.Conclusions: A discrete whole-genome methylation signature has been identified as molecular marker of prognosis for stage IIIC CM patients. Its use in daily practice is foreseeable, and promises to refine the comprehensive clinical management of stage III CM patients. © 2012 Sigalotti et al.; licensee BioMed Central Ltd.
Licastro D.,CBM scrl Genomics |
Gennarino V.A.,Telethon Institute of Genetics and Medicine |
Petrera F.,CBM scrl Genomics |
Sanges R.,CBM scrl Genomics |
And 3 more authors.
BMC Genomics | Year: 2010
Background: Ultraconserved elements (UCEs) are highly constrained elements of mammalian genomes, whose functional role has not been completely elucidated yet. Previous studies have shown that some of them act as enhancers in mouse, while some others are expressed in both normal and cancer-derived human tissues. Only one UCE element so far was shown to present these two functions concomitantly, as had been observed in other isolated instances of single, non ultraconserved enhancer elements.Results: We used a custom microarray to assess the levels of UCE transcription during mouse development and integrated these data with published microarray and next-generation sequencing datasets as well as with newly produced PCR validation experiments. We show that a large fraction of non-exonic UCEs is transcribed across all developmental stages examined from only one DNA strand. Although the nature of these transcripts remains a mistery, our meta-analysis of RNA-Seq datasets indicates that they are unlikely to be short RNAs and that some of them might encode nuclear transcripts. In the majority of cases this function overlaps with the already established enhancer function of these elements during mouse development. Utilizing several next-generation sequencing datasets, we were further able to show that the level of expression observed in non-exonic UCEs is significantly higher than in random regions of the genome and that this is also seen in other regions which act as enhancers.Conclusion: Our data shows that the concurrent presence of enhancer and transcript function in non-exonic UCE elements is more widespread than previously shown. Moreover through our own experiments as well as the use of next-generation sequencing datasets, we were able to show that the RNAs encoded by non-exonic UCEs are likely to be long RNAs transcribed from only one DNA strand. © 2010 Licastro et al; licensee BioMed Central Ltd.