EGAS00001000067-sc-20151012 - samples
Ontology highlight
ABSTRACT:
PROVIDER: EGAD00001001636 | EGA |
REPOSITORIES: EGA
Similar Datasets
Project description:15x whole genome sequencing in samples from the Cretan Greek isolate collection HELIC MANOLIS
| EGAD00001001897 | EGA
Project description:15x whole genome sequencing in samples from the Cretan Greek isolate collection HELIC MANOLIS
| EGAS00001001207 | EGA
Project description:The HELIC study has been whole genome sequencing individuals from 2 Greek isolated
populations at 1x depth. The genotype calling process crucially involves a VQSR step
followed by imputation-based refinement. We have been investigating optimal ways to
increase calling accuracy. To aid us in setting appropriate parameters for VQSR and other
QC steps, we have carried out whole exome sequencing of a small number of
HELIC samples.
| EGAD00001001638 | EGA
Project description:Whole-genome sequencing at 1x of samples from the Cretan Greek isolate collection HELIC-MANOLIS. Genome-wide association studies of complex traits have been successful in identifying common variant associations, but a substantial heritability gap remains. The field of complex trait genetics is shifting towards the study of low frequency and rare variants, which are hypothesised to have larger effects. The study of these variants can be empowered by focusing on isolated populations, in which rare variants may have increased in frequency and linkage disequilibrium tends to be extended. This work focuses on an isolated population from Crete, Greece. Sequencing is very efficient in isolated populations, because variants found in a few samples will be shared by others in extended haplotype contexts, supporting accurate imputation.
| EGAD00001001637 | EGA
Project description:Polyploidy is a widespread phenomenon in flowering plant species. Polyploid plants frequently exhibit considerable transcriptomic alterations after whole-genome duplication (WGD). It is known that the transcriptomic response to tetraploidization is ecotype-dependent in Arabidopsis. Nevertheless, the biological significance and the underlying mechanism are unknown. Here, we showed that 4x Col-0 and 4x Ler presented different flowering times, with a delayed flowering time in 4x Col-0 but not in 4x Ler. We found that the expression of FLOWERING LOCUS C (FLC), the major repressor of flowering, was significantly increased in 4x Col-0 but subtle change in 4x Ler. Moreover, the level of a repressive epigenetic mark, trimethylation of histone H3 at lysine 27 (H3K27me3), was significantly decreased in 4x Col-0 but not in 4x Ler, potentially leading to different transcription levels of FLC and flowering time in 4x Col-0 and 4x Ler. Apart from the FLC locus, hundreds of genes showed differentially H3K27me3 alterations in 4x Col-0 and 4x Ler. Comparably, LIKE HETEROCHROMATIN PROTEIN 1 (LHP1) and transcription factors required for H3K27me3 deposition presented differential transcriptional changes between 4x Col and Ler, potentially account for differential H3K27me3 alterations in 4x Col-0 and Ler. Last, we found that the natural 4x Arabidopsis ecotype Wa-1 presented early flowering time, associated with low expression and high H3K27me3 of FLC. Taken together, our results showed a role of H3K27me3 alterations in response to genome duplication in Arabidopsis autopolyploids and that flowering time variation potentially functions in autopolyploid speciation.
2022-01-01 | GSE185114 | GEO
Project description:The HELIC study has been whole genome sequencing individuals from 2 Greek isolated
populations at 1x depth. The genotype calling process crucially involves a VQSR step
followed by imputation-based refinement. We have been investigating optimal ways to
increase calling accuracy. To aid us in setting appropriate parameters for VQSR and other
QC steps, we have carried out whole exome sequencing of a small number of
HELIC samples.
| EGAS00001000602 | EGA
Project description:Isolated populations can empower the identification of rare variation associated with complex traits through next generation association studies. Here we have genotyped individuals from a Greek population isolate on the Illumina CoreExome Beadchip. The HELIC (Hellenic Isolated Cohorts) MANOLIS (Minoan Isolates) collection focuses on Anogia and surrounding Mylopotamos villages. Recruitment of this population-based sample was primarily carried out at the village medical centres. All individuals were older than 17 years and had to have at least one parent from the Mylopotamos area. www.helic.org
| EGAS00001000896 | EGA
Project description:Whole-genome sequencing at 1x of samples from the Cretan Greek isolate collection HELIC-MANOLIS. Genome-wide association studies of complex traits have been successful in identifying common variant associations, but a substantial heritability gap remains. The field of complex trait genetics is shifting towards the study of low frequency and rare variants, which are hypothesised to have larger effects. The study of these variants can be empowered by focusing on isolated populations, in which rare variants may have increased in frequency and linkage disequilibrium tends to be extended. This work focuses on an isolated population from Crete, Greece. Sequencing is very efficient in isolated populations, because variants found in a few samples will be shared by others in extended haplotype contexts, supporting accurate imputation.
| EGAS00001000392 | EGA
Project description:Isolated populations can empower the identification of rare variation associated with complex traits through next generation association studies. Here we have genotyped individuals from a Greek population isolate on the Illumina Human OmniExpress BeadChip array. The HELIC (Hellenic Isolated Cohorts) MANOLIS (Minoan Isolates) collection focuses on Anogia and surrounding Mylopotamos villages. Recruitment of this population-based sample was primarily carried out at the village medical centres. All individuals were older than 17 years and had to have at least one parent from the Mylopotamos area. www.helic.org **The data may not be used for population genetics analyses**
| EGAS00001000687 | EGA