BOL: Related items

Genomic architecture surrounding the fusion site of human chromosome 2

LEGE — Tue, 04 Mar 2025 12:26:29 -0600

The article "Genomic Structure and Evolution of the Ancestral Chromosome Fusion Site in 2q13–2q14.1 and Paralogous Regions on Other Human Chromosomes (https://pmc.ncbi.nlm.nih.gov/articles/PMC187548/)" explores the genomic architecture surrounding the fusion site of human chromosome 2. This fusion event is a key evolutionary marker distinguishing humans from other great apes, as humans have 46 chromosomes while chimpanzees, gorillas, and orangutans possess 48. The fusion occurred through an end-to-end joining of two ancestral chromosomes, which remain separate in nonhuman primates.

Key Findings:

Chromosomal Fusion and Its Molecular Signature:
- The fusion site is located at 2q13–2q14.1 and is characterized by degenerate telomeric sequences appearing interstitially, indicating the historical head-to-head joining of ancestral chromosomes.
- Despite being a signature of a past fusion event, these telomeric repeats are no longer functional and have undergone sequence degradation over time.
Extensive Duplications in the Surrounding Genomic Region:
- The study identifies large-scale segmental duplications flanking the fusion site, with several of these regions duplicated and scattered across multiple chromosomes.
- These duplications are predominantly located in subtelomeric and pericentromeric regions, suggesting their role in genomic instability and chromosomal evolution.
Paralogous Regions and Their Evolutionary Relationships:
- A 168-kilobase (kb) segment near the fusion site has 98%–99% sequence identity with three regions on chromosome 9 (9pter, 9p11.2, and 9q13).
- Another 67-kb region distal to the fusion site shows a high degree of homology to sequences in chromosome 22qter.
- Additionally, a 100-kb segment exhibits 96% sequence identity with a region in chromosome 2q11.2.
Comparative Genomics and Evolutionary Implications:
- By comparing the duplicated sequences and their arrangement in primates, the researchers traced the order of duplication events leading to their present distribution.
- The presence of specific repetitive elements within these duplicated segments serves as evolutionary markers that help infer their historical rearrangements.
- Some of these duplicated regions are associated with chromosomal inversion breakpoints, potentially contributing to evolutionary changes in primates.
- Recurrent structural rearrangements in these regions have been linked to human chromosomal disorders.

Conclusions and Implications:

The findings provide valuable insights into the structural evolution of human chromosome 2, which played a crucial role in human speciation.
Understanding these segmental duplications and their evolutionary trajectories sheds light on genomic instability, which may contribute to human genetic diseases.
The study highlights how large-scale chromosomal rearrangements, such as fusion and duplication, have influenced the evolutionary divergence of humans from other primates.

This research advances our understanding of human genome evolution and offers a foundation for studying the effects of structural variants in genetic disorders.

Lifemap

Jit — Mon, 10 Apr 2017 05:42:37 -0500

Lifemap is an interactive tool to explore the WHOLE NCBI TAXONOMY. The concept used in Lifemap is similar to the one used in cartography with tools like Google Maps© or Open Street Maps: exploring is done by zooming and panning.

The current tree contains ALL species present in NCBI taxonomy as of October 18th, 2016: 1,135,169 species including 10,545 Archaea, 418,777 Bacteria and 705,847 Eukaryotes. The Lifemap tree is updated every two weeks.

All the nodes in the tree are clickable. This displays various information and options:

The species name (and the associated common name if there is one)
The rank (kingdom, family, class, species...)
Ability to go to the corresponding node/species on NCBI web site (displayed in a new window)
Possibility to download the corresponding subtree in newick extended format
Possibilty to get the whole lineage from the current node/tip to the root of the tree.

Address of the bookmark: http://lifemap-ncbi.univ-lyon1.fr/

Interactive Bioinformatics Resources !

Jit — Thu, 12 Aug 2021 00:09:00 -0500

Learn how to use bioinformatics tools right from your browser.
Everything runs in a sandbox, so you can experiment all you want.

More at sandbox.bio

Address of the bookmark: http://sandbox.bio

Leaflet: JavaScript libraries for interactive maps

Jit — Mon, 10 Feb 2020 01:35:07 -0600

Leaflet is one of the most popular open-source JavaScript libraries for interactive maps.

Features

Interactive panning/zooming
Compose maps using arbitrary combinations of:
- Map tiles
- Markers
- Polygons
- Lines
- Popups
- GeoJSON
Create maps right from the R console or RStudio
Embed maps in knitr/R Markdown documents and Shiny apps
Easily render spatial objects from the sp or sf packages, or data frames with latitude/longitude columns
Use map bounds and mouse events to drive Shiny logic
Display maps in non spherical mercator projections
Augment map features using chosen plugins from leaflet plugins repository

https://rstudio.github.io/leaflet/

Address of the bookmark: https://rstudio.github.io/leaflet/

Des Higgins: Visualizing Multiple Sequence Alignments

Wed, 26 Feb 2014 00:50:08 -0600

Copyright Broad Institute, 2013. All rights reserved. Des Higgins (http://www.bioinf.ucd.ie) gives a very entertaining introduction to the visualization of multiple sequence alignment, and to his widely-used Clustal tool. He highlights the emerging challenge of managing alignments with a very large number of sequences, and presents several approaches to this challenge, including faster algorithms and abstract views of clusters of alignments. This talk was presented at VIZBI 2011, an international conference series on visualizing biological data (http://www.vizbi.org) funded by NIH & EMBO. For information about data visualization efforts at the Broad Institute, please visit: http://www.broadinstitute.org/node/1363/

MEDEA: Comparative Genomic Visualization with Adobe Flash

Jit — Tue, 26 Apr 2016 12:15:16 -0500

As the number of sequence and annotated genomes grows larger, the need to understand, compare, and contrast the data becomes increasingly important. Using the power of the human visual system to detect trends and spot outliers is necessary in such large and complex data sets.

More at http://www.broadinstitute.org/annotation/medea/

Address of the bookmark: http://www.broadinstitute.org/annotation/medea/

Anvio

Shruti Paniwala — Thu, 16 Jun 2016 18:15:41 -0500

In a nutshell

Anvi’o is an analysis and visualization platform for ‘omics data.

Please find the methods paper here: https://peerj.com/articles/1319/

Anvi’o would not have been possible without the help of many people who directly or indirectly contributed to its development. Here is the acknowledgements section of our methods paper

An analysis and visualization platform for 'omics data http://merenlab.org/projects/anvio

Paper https://peerj.com/articles/1839/

Address of the bookmark: https://github.com/meren/anvio

Fancy Oneliner for Bioinformatics !!

Poonam Mahapatra — Thu, 07 Jul 2016 12:05:50 -0500

This webpage lists some of the one-liners that we frequently use in metagenomic analyses. You can click on the following links to browse through different topics. You can copy/paste the commands as they are in your terminal screen, provided you follow the same naming conventions and folder structures as we have. We are sharing these codes with the intention that if they are useful and help you in your analyses, then we will be appropriately credited as considerable effort has been put into devising them.

Address of the bookmark: http://userweb.eng.gla.ac.uk/umer.ijaz/bioinformatics/oneliners.html

ETE 3: Reconstruction, Analysis, and Visualization of Phylogenomic Data

Jit — Mon, 19 Feb 2018 06:46:15 -0600

ETE v3, featuring numerous improvements in the underlying library of methods, and providing a novel set of standalone tools to perform common tasks in comparative genomics and phylogenetics.

The new features include

(i) building gene-based and supermatrix-based phylogenies using a single command,

(ii) testing and visualizing evolutionary models,

(iii) calculating distances between trees of different size or including duplications, and

(iv) providing seamless integration with the NCBI taxonomy database.

ETE is freely available at http://etetoolkit.org

Address of the bookmark: http://etetoolkit.org

D3 javascript for visualization !

Jit — Mon, 23 Apr 2018 08:42:22 -0500

Welcome to the D3 gallery! More examples are available on bl.ocks.org/mbostock. If you want to share an example and don't have your own hosting, consider using Gist and bl.ocks.org. If you want to share or view live examples try vida.io.

Address of the bookmark: https://github.com/d3/d3/wiki/Gallery