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Xian Chang

@xian-chang.bsky.social

Bioinformatics postdoc at INRAE in Toulouse, France. Working on data structures and algorithms for pangenome graphs

157 Followers  |  136 Following  |  9 Posts  |  Joined: 23.11.2024  |  2.069

Latest posts by xian-chang.bsky.social on Bluesky

@acarroll.bsky.social @kishwar.bsky.social Pi-Chuan Chang, Faith Okamoto, @humanpangenome.bsky.social

02.10.2025 06:40 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

Big thanks to everyone involved in the paper! @benedictpaten.bsky.social @adamnovak.graphs.vg Jordan Eizenga @jltsiren.bsky.social @jmonlong.bsky.social @shlokanegi.bsky.social Francesco
Andreace @sagorika03.bsky.social @kokyriakidis.bsky.social Glenn Hickey, Stephen Hwang, Emmanuele Delot

02.10.2025 06:40 β€” πŸ‘ 2    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0
A cartoon of a variation graph and a sequencing read with seed alignments between the read and graph. The snarl tree corresponding to the variation graph is shown to the right. Below is the zip code tree representing the seeds, snarl and chain boundaries, and the distances among them.

A cartoon of a variation graph and a sequencing read with seed alignments between the read and graph. The snarl tree corresponding to the variation graph is shown to the right. Below is the zip code tree representing the seeds, snarl and chain boundaries, and the distances among them.

My favorite part: co-linear chaining in cyclic graphs using zip code trees, a new data structure for quickly finding distances in the graph that best match corresponding distances in the read

02.10.2025 06:40 β€” πŸ‘ 5    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

Also featuring a cool demo of pangenome-guided regional assembly of complex loci from @shlokanegi.bsky.social Francesco Andreace @sagorika03.bsky.social @kokyriakidis.bsky.social

02.10.2025 06:31 β€” πŸ‘ 2    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

πŸ¦’Long read giraffe is out!πŸ¦’
Mapping long reads to pangenome graphs is ~10x faster than with GraphAligner, with veeery slightly better mapping accuracy, short variant calling, and SV genotyping than GraphAligner or Minimap2

02.10.2025 06:28 β€” πŸ‘ 41    πŸ” 22    πŸ’¬ 1    πŸ“Œ 0

Republicans are shutting down the government to stop you from having healthcareβ€”there’s the message!!!!

01.10.2025 14:47 β€” πŸ‘ 1    πŸ” 1    πŸ’¬ 0    πŸ“Œ 0
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Last talk of the day (before posters) "Lossless Pangenome Indexing Using Tag Arrays" presented by Parsa Eskandar! #WABI25

20.08.2025 19:59 β€” πŸ‘ 11    πŸ” 3    πŸ’¬ 0    πŸ“Œ 0

Thanks so much!

22.03.2025 07:07 β€” πŸ‘ 0    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

Huge thank you to my incredible advisor @benedictpaten.bsky.social at @ucscgenomics.bsky.social for all his support and guidance, and to my committee David Haussler, @russcd.bsky.social, and @jianma.bsky.social

21.03.2025 23:02 β€” πŸ‘ 4    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0
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I'm very excited to share that I defended my thesis this week! I helped develop algorithms to combat reference #bias and make genomics more #equitable and #representative by incorporating genetic #diversity into genomics pipelines

21.03.2025 23:00 β€” πŸ‘ 9    πŸ” 1    πŸ’¬ 1    πŸ“Œ 0
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Personalized pangenome references - Nature Methods This work introduces a k-mer-based approach to customizing a pangenome reference, making it more relevant to a new sample of interest. This method enhances the accuracy of genotyping small variants an...

We use personalized references with our Giraffe aligner. Each chromosome is partitioned into a sequence of blocks. We sample the most relevant haplotypes in each block using kmer counts. Mapping to this personalized reference improves variant calling accuracy. www.nature.com/articles/s41...

04.03.2025 23:00 β€” πŸ‘ 17    πŸ” 8    πŸ’¬ 1    πŸ“Œ 0
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Welcome to the Bluesky account for Stand Up for Science 2025!

Keep an eye on this space for updates, event information, and ways to get involved. We can't wait to see everyone #standupforscience2025 on March 7th, both in DC and locations nationwide!

#scienceforall #sciencenotsilence

12.02.2025 17:04 β€” πŸ‘ 11535    πŸ” 5480    πŸ’¬ 291    πŸ“Œ 677
Variation graph representing the names of long read pangenome mappers: MiniGraph, GraphChainer, GraphAligner, PanAligner, and Giraffe

Variation graph representing the names of long read pangenome mappers: MiniGraph, GraphChainer, GraphAligner, PanAligner, and Giraffe

New figure for my thesis showing why Giraffe is the best long read pangenome mapper. No further evidence will be provided.

14.02.2025 19:45 β€” πŸ‘ 4    πŸ” 1    πŸ’¬ 1    πŸ“Œ 0
Quote: Long read sequencing is likely the next best test for unsolved cases... It can serve as a single diagnostic test, reducing the need for multiple clinical visits and transforming a years-long diagnostic journey into a matter of hours. Shloka Negi, UC Santa Cruz

Quote: Long read sequencing is likely the next best test for unsolved cases... It can serve as a single diagnostic test, reducing the need for multiple clinical visits and transforming a years-long diagnostic journey into a matter of hours. Shloka Negi, UC Santa Cruz

Researchers at @ucsantacruz.bsky.social have demonstrated how long-read sequencing could improve detection of diseases that have eluded diagnosis, at a fraction of the cost. New clinical tests could be on the way.
πŸ—ž news.ucsc.edu/2025/01/pate...
πŸ‘πŸΌπŸ‘πŸΏπŸ‘πŸΎ @khmiga.bsky.social @benedictpaten.bsky.social

24.01.2025 19:17 β€” πŸ‘ 15    πŸ” 7    πŸ’¬ 0    πŸ“Œ 1

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