Comparing existing DNA LLMs to Cognit’s LGM: Mathematical Highlights

Freedom Preetham
Meta Multiomics
Published in
7 min readNov 15, 2023

In the rapidly evolving field of genomics, particularly in oncogenomics, the comparison between DNA Large Language Models (LLMs) like Hyena DNA, DNABert, or Nucleotide-Transformer and Cognit’s Large Genomic Model (LGM) necessitates a deeper exploration into frameworks and advanced mathematical formulations.

This scientific blog aims to provide a mathematically expressive analysis, highlighting the enhanced capabilities of Cognit’s LGM through mathematical underpinnings as a governing expression and comparisons.

DNA LLMs Limitations

At the heart of modern genomic analysis lies a critical distinction: the complexity of genomic grammar. Traditional DNA LLMs, as explored in our comprehensive blog series “N-Dimensional Genomic Grammar vs One-Dimensional Linguistic Grammar,” are fundamentally constrained by their reliance on one-dimensional grammar.

DNA LLMs, primarily uses k-mers and sequence length warm-ups to predict de-novo DNA sequences and enhancer-promoter influences, falls significantly short in the multifaceted realm of Oncogenomics.

The Inadequacy of DNA LLMs in Oncogenomics: A Closer Look

As of this writing, DNA LLMs such as HyenaDNA, having input context length of 1MB, are limited to handling 919 binary outputs for chromatin accessibility, cluster the functional annotation, and enable species classification.

However, the field of Oncogenomics demands far more. It requires a model that transcends beyond mere enhancer-promoter influence, delving into the intricacies of gene expression with a minimum accuracy threshold of 0.7 to be deemed useful. Clustering functional annotations or species classification are not readily helpful.

The Comprehensive Requirements for Oncogenomic Analysis:

  1. Gene Product: The model should accurately predict gene expression and TSS binding sites.
  2. Multi-Faceted Interaction Analysis: The model must elucidate protein-DNA interactions, protein-protein interactions, and histone modifications.
  3. Chromatin Dynamics: Active chromatin regions and topologically accessible domains per gene locus are essential for a holistic understanding.
  4. Single-Cell Resolution: Incorporation of single-cell ATAC sequences is vital for detailed genomic insights.
  5. Cell Type and Condition Specificity: The ability to predict across multiple cell types and under varying conditions (disease states, cell signals, nutrient levels, methylation status, treatment regimes) is non-negotiable.

None of the current DNA LLMs enbales these capabilities.

Context Length Limitation:

Mathematical Underpinning

In this equation:

  • L_DNA​ represents the context length limitation in DNA Large Language Models.
  • The summation ∑ i=1 to N​ iterates over N nucleotide sequences.
  • li​ denotes the length of each nucleotide sequence.
  • αi​ symbolizes the information entropy of each nucleotide sequence, adding a layer of complexity to the original context length limitation.

This equation is meticulously designed to account for both the length and the information density of genomic sequences, highlighting the limitations in processing high-entropy genomic data — a critical aspect in oncogenomics. It underscores the challenges faced in managing complex genomic information, which is essential for advanced research in the field.

Specifically, this limitation becomes evident in the context of current DNA LLMs like Hyena DNA, which are constrained to 1MB context lengths and primarily focus on outputting de-novo sequences or species classification. This constraint significantly limits their applicability in the nuanced and data-intensive domain of oncogenomic studies, where the ability to process and interpret high-entropy genomic data is paramount.

Binary Output Limitation:

Mathematical Underpinning

​In this equation:

  • O_DNA​ represents the output complexity in DNA Large Language Models.
  • The summation ∑ i=1 to n​ iterates over n genomic features.
  • 2^fi​ is an exponential function where fi​ represents the function mapping each genomic feature to its binary output.

This equation highlights the exponential increase in complexity when dealing with multiple genomic features, emphasizing the inadequacy of binary outputs in capturing the full spectrum of genomic information, which is particularly relevant in the field of oncogenomics.

Implication: The exponential nature of this function illustrates the complexity increase when dealing with multiple genomic features, underscoring the inadequacy of binary outputs in capturing the full spectrum of genomic information.

Cognit LGM’s Advanced Capabilities

In stark contrast, Cognit’s Large Genomic Model (LGM) emerges as a groundbreaking solution. Engineered from the ground up, Cognit’s LGM embraces the complexity of n-dimensional genomic grammar.

Cognit is built as a cross-cell, cross-species genomic model that can replicate all the desired assays, gene products, protein-dna interactions, PPI, de-novo annotations, diseased conditions, GRN events and treatment regiems as an output, just from a DNA input.

Read that again slowly to comprehend the intricate and powerful nature of a Large Genomic Model.

Here is example of a single species, intermediaries. Now imagine multiple such hyper-cubes for every species.

This innovative approach enables the LGM to proficiently address the multifaceted requirements of Oncogenomics. From predicting intricate gene interactions to adapting to diverse cellular conditions, Cognit’s LGM stands as a testament to pioneering genomic modeling, setting a new standards in the field.

Cross-Species & Cell Type Adaptability:

Mathematical Underpinnings

In this equation:

  • C_adapt​ symbolizes the adaptability of the model across different species and cell types.
  • The double integral ∫S​∫C​ signifies the integration over the domains of species (S) and cell types (C).
  • f(s,c) is a function that represents the adaptability of the model to a specific species s and cell type c.
  • ds and dc are the differential elements for species and cell types, respectively.

This equation is designed to mathematically express the concept of cross-species and cell type adaptability, a key feature of advanced genomic models like Cognit’s LGM. It encapsulates the continuous and comprehensive nature of the model’s adaptability across various biological dimensions.

Tissue-Specific Insight:

Mathematical Underpinnings

In this equation:

  • T_specific​ represents the tissue-specific insight capability of the model.
  • The integral ∫T​ indicates integration over the domain of tissue types T.
  • e^λt is an exponential decay factor, where λ is a constant that determines the rate of decay and t represents tissue-specific factors.
  • g(t) is a function that models the influence of tissue-specific factors.
  • dt is the differential element for tissue types.

This equation models the nuanced and diminishing influence of distant tissue-specific factors, essential for accurate gene expression predictions in diverse cellular environments. This equation incorporates an exponential decay factor to represent the complex interactions in tissue-specific genomic analysis.

Epigenetic Optimizers:

Mathematical Underpinnings

In this equation:

  • E_opt​ represents the epigenetic optimization capability of the model.
  • The summation ∑e=1E​ iterates over E epigenetic factors.
  • we​ is the weight or significance of each epigenetic factor.
  • xe​ denotes the state or value of the epigenetic factor.
  • h(e) is a function that models the impact of the epigenetic factor on gene expression or regulation.

This equation encapsulates the complex interplay of various epigenetic factors in gene regulation, highlighting the sophisticated approach of models like Cognit’s LGM in considering epigenetic influences.Implication: This equation incorporates the complex interplay of histone modifications, crucial for understanding gene expression landscapes.

Feedback Mechanism Analysis:

Mathematical Underpinnings:

In this equation:

  • F_feedback​ represents the feedback mechanism analysis capability of the model.
  • The term (/dt²)​Y is a second-order differential equation, indicating the rate of change of the rate of change (acceleration) of a variable Y with respect to time t.
  • f(X,Y,dY/dt​) is a function that models the dynamic feedback mechanism, where X and Y are variables representing states or quantities in the system, and dY/dt​ is the first derivative of Y with respect to t, representing the rate of change of Y.

This equation is designed to mathematically model the dynamic and accelerated feedback mechanisms in cellular processes, capturing the complex, time-dependent nature of cellular feedback mechanisms.

Genomic Interaction Proficiency:

Mathematical Underpinnings:

In this equation:

  • G_interact​ represents the genomic interaction proficiency of the model.
  • The double summation ∑ i=1n​ ∑ ji​​ iterates over all pairs of genes gi​ and gj​, ensuring that i is not equal to j to avoid self-interaction.
  • ϕ(gi​,gj​) is a function that models the interaction between genes gi​ and gj​.
  • ψ(i,j) represents a function that accounts for the spatial and functional proximity or relationship between the genes gi​ and gj​.

This equation is designed to capture the complex interactions between different genes, considering both their spatial and functional relationships, which is crucial in understanding genomic interactions and their implications in biological systems.

Open Discussion:

The exploration of the mathematical underpinnings in this study opens up a dialogue about the capabilities and limitations of both DNA Large Language Models (LLMs) and Cognit’s Large Genomic Model (LGM). These equations shed light on the complex nature of genomic data and the models that are required execute such governing functions, especially in the field of oncogenomics.

This discussion invites further consideration of how Cognit’s LGM, with its ability to handle intricate genomic interactions, epigenetic factors, and dynamic cellular processes, aligns with the specific demands of oncogenomics research. The mathematical underpinnings presented here offer an insight into the capabilities of Cognit’s LGM, posing the question of whether current DNA LLMs can match up to the comprehensive and nuanced approach needed for precision oncology.

We encourage an open exchange of ideas and perspectives on how these models can evolve and potentially collaborate to advance the field of genomic research. This conversation is not only about comparing these models but also about envisioning the future directions and potential integrations that could redefine the landscape of genomic analysis and oncogenomic studies.

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