Sequence homology

The shared evolutionary ancestry of DNA, RNA or protein sequences, inferred from statistically and structurally supported similarity but treated as a historical relation rather than a percentage-valued resemblance.

Version

v1 · 2026-09-08 · History

Domain-specific #

6664

Origin domain

evolutionary bioinformatics

Subdomain

molecular homology

Core Idea

Sequence homology is common evolutionary origin of sequence regions, arising through speciation, duplication or horizontal transfer and inferred rather than numerically measured as a fraction. Mutation and rearrangement modify descendant sequences while preserving statistically detectable correspondence; alignment and phylogenetic context support an ancestry hypothesis and distinguish event types. The abstraction is therefore identified by a declared carrier, a transformation or constraint over that carrier, and an invariant that tells an analyst whether the named structure is genuinely present.

The load-bearing residual is not the broad topic of evolutionary bioinformatics. It is historical common descent of molecular sequences and its event-qualified ortholog, paralog and xenolog relations.

Scope of Application

Sequence homology belongs to evolutionary bioinformatics and is useful where the analyst can specify two or more biological sequences, an alignment, an evolutionary model, ancestry events, similarity evidence and an orthology/paralogy/xenology classification, then evaluate the claim is binary shared ancestry for specified sequence regions and is supported by alignment and evolutionary evidence, not merely a high percent identity. The scope is broad within that domain but bounded by the need for the claim is binary shared ancestry for specified sequence regions and is supported by alignment and evolutionary evidence, not merely a high percent identity. This entry concerns inferential concepts and sequence interpretation; it provides no laboratory, synthesis, pathogen, or engineering procedure.

Clarity

The abstraction clarifies a crowded vocabulary by making the claim is binary shared ancestry for specified sequence regions and is supported by alignment and evolutionary evidence, not merely a high percent identity the center of the account. A claim should name the carrier, the governing operation or relation, the applicable assumptions, and the recognition test. A bare label is insufficient because the name Sequence homology can be used for a formal identity, an implementation, or a neighboring result unless carrier and convention are stated.

Manages Complexity

Without the abstraction, an analyst must reason directly over many local details: the carrier roles, admissibility assumptions, competing conventions, derived invariants, boundary cases, and proof or validation obligations specific to Sequence homology. Sequence homology compresses them into the roles in the structural signature. That compression permits comparison across instances without erasing the variables that determine validity. It also exposes which details may be varied safely and which are constitutive.

Abstract Reasoning

1. Identify the carrier. State what the elements, states, objects, or observations are: two or more biological sequences, an alignment, an evolutionary model, ancestry events, similarity evidence and an orthology/paralogy/xenology classification. Reject examples whose alleged carrier belongs to a different problem. 2. Lock the constitutive rule. Express the claim is binary shared ancestry for specified sequence regions and is supported by alignment and evolutionary evidence, not merely a high percent identity independently of one notation or implementation.

Knowledge Transfer

Knowledge transfers strongly among subfields of evolutionary bioinformatics because they reuse two or more biological sequences, an alignment, an evolutionary model, ancestry events, similarity evidence and an orthology/paralogy/xenology classification, Mutation and rearrangement modify descendant sequences while preserving statistically detectable correspondence; alignment and phylogenetic context support an ancestry hypothesis and distinguish event types., and type the carrier, state every parameter and convention in the definition, test that the claim is binary shared ancestry for specified sequence regions and is supported by alignment and evolutionary evidence, not merely a high percent identity, compare the nearest accepted identity, and report counterexamples, uncertainty, and limiting cases.

Relationships to Other Abstractions

Current abstraction Sequence homology Domain-specific

Parents (1) — more general patterns this builds on

• Sequence homology is a kind of Inheritance Prime

  The proposed strict upward parent is prime:inheritance.

Hierarchy path (1) — routes to 1 parentless root

• Sequence homology → Inheritance → Dependency

Neighborhood in Abstraction Space

Sequence homology sits in a crowded region of the domain-specific corpus (22^nd percentile for distinctiveness): several abstractions share nearly its structure, so a description that fits it tends to fit its neighbors too.

Family — Speciation & Phylogenetic Inference (14 abstractions)

Nearest neighbors

• Most recent common ancestor — 0.93
• Phylogenetic bracketing — 0.92
• Allopatric speciation — 0.91
• Deep homology — 0.91
• Ka/Ks ratio — 0.90

Computed from structural-signature embeddings · 2026-09-08