Austin Wang
austintwang.bsky.social
Austin Wang
@austintwang.bsky.social
Stanford CS PhD student working on ML/AI for genomics with @anshulkundaje.bsky.social

austintwang.com
I think that’ll be interesting to look more into! The profile information does not convey overall accessibility since it’s normalized, but maybe this sort of multitasking could help.
December 14, 2024 at 3:24 PM
Thank you for the kind words! Yes, ChromBPNet uses unmodified models, which includes profile data and a bias model. However these evaluations use only the count head.
December 11, 2024 at 6:14 AM
(9/10) How do we train more effective DNALMs? Use better data and objectives:
• Nailing short-context tasks before long-context
• Data sampling to account for class imbalance
• Conditioning on cell type context
These strategies use external annotations, which are plentiful!
December 11, 2024 at 2:30 AM
(8/10) This indicates that DNALMs inconsistently learn functional DNA. We believe that the culprit is not architecture, but rather the sparse and imbalanced distribution of functional DNA elements.

Given their resource requirements, current DNALMs are a hard sell.
December 11, 2024 at 2:30 AM
(7/10) DNALMs struggle with more difficult tasks.
Furthermore, small models trained from scratch (<10M params) routinely outperform much larger DNALMs (>1B params), even after LoRA fine-tuning!
Our results on the hardest task - counterfactual variant effect prediction.
December 11, 2024 at 2:30 AM
(6/10) We introduce DART-Eval, a suite of five biologically informed DNALM evaluations focusing on transcriptional regulatory DNA ordered by increasing difficulty.
December 11, 2024 at 2:30 AM

(5/10) Rigorous evaluations of DNALMs, though critical, are lacking. Existing benchmarks:
• Focus on surrogate tasks tenuously related to practical use cases
• Suffer from inadequate controls and other dataset design flaws
• Compare against outdated or inappropriate baselines
December 11, 2024 at 2:30 AM
(4/10) An effective DNALM should:
• Learn representations that can accurately distinguish different types of functional DNA elements
• Serve as a foundation for downstream supervised models
• Outperform models trained from scratch
December 11, 2024 at 2:30 AM
(3/10) However, DNA is vastly different from text, being much more heterogeneous, imbalanced, and sparse. Imagine a blend of several different languages interspersed with a load of gibberish.
December 11, 2024 at 2:30 AM
(2/10) DNALMs are a new class of self-supervised models for DNA, inspired by the success of LLMs. These DNALMs are often pre-trained solely on genomic DNA without considering any external annotations.
December 11, 2024 at 2:30 AM