1. The trans-ancestral genomic architecture of glycemic traits
Hugoline G de Haan, et al. Nat Genet. 2021 Jun;53(6):840-860. doi: 10.1038/s41588-021-00852-9. Epub 2021 May 31.
Glycemic traits are used to diagnose and monitor type 2 diabetes and cardiometabolic health. To date, most genetic studies of glycemic traits have focused on individuals of European ancestry. Here we aggregated genome-wide association studies comprising up to 281,416 individuals without diabetes (30% non-European ancestry) for whom fasting glucose, 2-h glucose after an oral glucose challenge, glycated hemoglobin and fasting insulin data were available. Trans-ancestry and single-ancestry meta-analyses identified 242 loci (99 novel; P < 5 × 10-8), 80% of which had no significant evidence of between-ancestry heterogeneity. Analyses restricted to individuals of European ancestry with equivalent sample size would have led to 24 fewer new loci. Compared with single-ancestry analyses, equivalent-sized trans-ancestry fine-mapping reduced the number of estimated variants in 99% credible sets by a median of 37.5%. Genomic-feature, gene-expression and gene-set analyses revealed distinct biological signatures for each trait, highlighting different underlying biological pathways. Our results increase our understanding of diabetes pathophysiology by using trans-ancestry studies for improved power and resolution.
2. Heterochiral dipeptide d-phenylalanyl- l-phenylalanine (H-D Phe-L Phe-OH) as a potential inducer of metastatic suppressor NM23H1 in p53 wild-type and mutant cells
Mir Mohd Faheem, Junaid Ur Rahim, Syed Mudabir Ahmad, Khalid Bashir Mir, Gursimar Kaur, Madhulika Bhagat, Rajkishor Rai, Anindya Goswami Mol Carcinog. 2022 Dec;61(12):1143-1160. doi: 10.1002/mc.23465. Epub 2022 Oct 14.
In recent years, significant progress has been made to the use-case of small peptides because of their diversified edifice and hence their versatile application scope in cancer therapy. Here we identify the heterochiral dipeptide H-D Phe-L Phe-OH (F1) as a potent inducer of the metastatic suppressor NM23H1. We divulge the effect of F1 on the major EMT/metastasis-associated genes and the implications on the invasion and migration ability of cancer cells. The anti-invasive potential of F1 was directly correlated with NM23H1 expression. Mechanistically, F1 treatment elevated p53 levels as validated by localization and transcriptional studies. In the NM23H1 knockdown condition, F1 failed to induce any p53 expression/nuclear localization, indicating that the upregulation in p53 expression by F1 is NM23H1 dependent. We also demonstrate how the antimetastatic potential of F1 is primarily mediated through NM23H1 irrespective of the p53 status of the cell. However, both NM23H1 and a functional p53 protein in conjunction govern the apoptotic and cytostatic potential of F1. Coimmunoprecipitation studies unraveled the augmentation of the p53 and NM23H1 interaction in p53 wild-type cells. However, in p53 mutated cells, no such enrichment was evidenced. We employed mouse isogenic cell lines (4T-1 and 4T-1 p53) to determine the in vivo efficacy of F1 (spontaneous and experimental models). Decreased tumor volume in the cohort injected with 4T-1 p53 cells demonstrated that while the antimetastatic potential of F1 was reliant on NM23H1, p53 activation was required for ablation of primary tumor burden. Our findings unravel that F1 treatment induces significant abrogation of the migration, invasion and metastatic potential of both p53 wild-type and p53 deficient cancers mediated through NM23H1.
3. A saturated map of common genetic variants associated with human height
Gabriel Cuellar Partida, Yan Sun, Damien Croteau-Chonka, Judith M Vonk, Stephen Chanock, Loic Le Marchand Nature. 2022 Oct;610(7933):704-712. doi: 10.1038/s41586-022-05275-y. Epub 2022 Oct 12.
Common single-nucleotide polymorphisms (SNPs) are predicted to collectively explain 40-50% of phenotypic variation in human height, but identifying the specific variants and associated regions requires huge sample sizes1. Here, using data from a genome-wide association study of 5.4 million individuals of diverse ancestries, we show that 12,111 independent SNPs that are significantly associated with height account for nearly all of the common SNP-based heritability. These SNPs are clustered within 7,209 non-overlapping genomic segments with a mean size of around 90 kb, covering about 21% of the genome. The density of independent associations varies across the genome and the regions of increased density are enriched for biologically relevant genes. In out-of-sample estimation and prediction, the 12,111 SNPs (or all SNPs in the HapMap 3 panel2) account for 40% (45%) of phenotypic variance in populations of European ancestry but only around 10-20% (14-24%) in populations of other ancestries. Effect sizes, associated regions and gene prioritization are similar across ancestries, indicating that reduced prediction accuracy is likely to be explained by linkage disequilibrium and differences in allele frequency within associated regions. Finally, we show that the relevant biological pathways are detectable with smaller sample sizes than are needed to implicate causal genes and variants. Overall, this study provides a comprehensive map of specific genomic regions that contain the vast majority of common height-associated variants. Although this map is saturated for populations of European ancestry, further research is needed to achieve equivalent saturation in other ancestries.