Kari Lavikka

Kari Lavikka

@karilavikka.fi

Researcher working on bioinformatics, WebGL-powered cancer genome visualization, and tumor evolution.

69 followers146 following33 posts

GenomeSpy is an open-source toolkit for building interactive genome visualizations using a declarative grammar. A bit like ggplot2, but primarily for genome-aligned data with smooth interactivity. It also includes an application for exploring multi-sample genomic datasets, such as cancer cohorts.

I made an R package that creates oncoplots, lollipop plots, rainfall plots, and GISTIC plots with basic interactivity such as tooltips and zooming. It's almost a drop-in replacement for the corresponding maftools' plotting functions.

View full thread

I made an R package that creates oncoplots, lollipop plots, rainfall plots, and GISTIC plots with basic interactivity such as tooltips and zooming. It's almost a drop-in replacement for the corresponding maftools' plotting functions.

But why? There are a few reasons. Those huge oncoplot/oncoprint matrices look impressive, like Circos plots do, but they become barely readable once you throw enough data at them. Maybe interactivity helps. (PDFs are still static, though 🤔.)

When doing copy-number analysis, have you ever struggled to interpret ASCAT sunrise plots and similar purity/p​​loidy grids? Have you wanted to compare how different solutions affect the allele-specific copy-number fit and better understand the fitting procedure?

View full thread

When doing copy-number analysis, have you ever struggled to interpret ASCAT sunrise plots and similar purity/p​​loidy grids? Have you wanted to compare how different solutions affect the allele-specific copy-number fit and better understand the fitting procedure?

I implemented an interactive GenomeSpy visualization for this purpose. You can play with different samples from the simulated ASCAT example data and see how the choice of purity, ploidy, and other settings affects the estimated allele-specific copy numbers.

I recently added a parameterizable arrow mark to GenomeSpy, my open-source toolkit for interactive genomic data visualization, and implemented a couple of fancy examples to showcase it. (1/3)

A reference sequence translated into amino acids in all three reading frames on both strands, and a simple read-alignment viewer for BAM files. They also use some new data transformations I added to the visualization grammar. (2/3)

Kari Lavikka reposted

see you in 1 hour! #BioVis #DataVis meetup

Helena Klara Jambor@helenajambor.bsky.social

💥 First #BioVis meetup of 2026 💥 #DataVis “Crafting visual biomedical stories“ with Laura Garrison, University of Bergen - Virtual, no registration, link/more info: biovis.net/2026/meetup/... - Wednesday, 21. January, 5pm Berlin/4pm London

Parquet and Arrow are great columnar formats, but the abysmal performance of TextDecoder on Chrome (or maybe V8) completely kills any speed benefits when files contain lots of short, unique strings. Even #JavaScript CSV parsers are faster. It’s fine if you don’t need to access the string columns 🤷

It’s been a bit quiet on the GenomeSpy front, but I finally had time to implement interval selections and other fancy features. Vega-Lite–style conditional encodings are compiled into shader code, with selection tests running on the GPU—making interactions snappy. (1/2)

Selections can also drive filtering and aggregation, though the code is still entirely CPU-based for now. I’d like to explore columnar and GPU-based approaches in the future. (2/2)

I've typically used R (with tidyverse) for analyses, but recently I've been familiarizing myself with Python. Pandas feels quite awkward to me, at least compared to dplyr. But @pola.rs is great! It works wonderfully with Parquet files too. ❤️

Finally, I'm grateful to all the collaborators and supervisors on this and the previous tumor evolution papers and the whole tumor evolution team! (7/7)

Metastases in solid tumors consist of heterogeneous subclonal mixtures that evolve across space and time. Jellyfish integrates tumor phylogeny and subclonal compositions of spatiotemporal samples into a unified plot, making subclonal dynamics easier to interpret. #CancerResearch (2/7)

My first first-author paper is now published: doi.org/10.1093/giga.... GenomeSpy is a grammar-based visualization toolkit for genomic data, powered by efficient WebGL rendering. Check the paper for examples on how we use it to explore a large ovarian high-grade serous carcinoma dataset.

academic.oup.comDeciphering cancer genomes with GenomeSpy: a grammar-based visualization toolkitAbstractBackground. Visualization is an indispensable facet of genomic data analysis. Despite the abundance of specialized visualization tools, there remai

You are up to date.