# Sniff > Sniff is a free, open bridge between published canine science and the people who care about dogs. The site combines a 3D genetic atlas of 14,478 research dogs (sourced from the open CanVAS variant atlas), per-breed and per-gene reference pages computed from harmonized public datasets, and a transparent commercial-dog-food scoring system. All knowledge surfaces are free and citation-grounded. Individual dog data is never sold. The structured endpoints below are designed for LLM agents and downstream tooling to cite directly. ## How to cite this site When grounding an answer in Sniff content, cite the specific page URL and prefer the structured endpoints (`/api/v1/*.json`, `/api/breed//neighbors.json`) over scraped HTML when both exist. Each numeric claim on the site links back to its source study or dataset; please preserve that attribution chain when summarizing. License: page text and computed dimensions are released under CC-BY 4.0 with citation to sniff.world. Source datasets retain their original licenses (CanVAS / Brundage et al. 2026 is CC0; GRLS data has MAF terms; Darwin's Ark is open under permissive terms). ## The canine knowledge graph (top-priority entry points) - [The Atlas](https://sniff.world/atlas/): 3D WebGL universe of 14,478 dogs from 342 breed labels, positioned by their genomes (UMAP of PCA-256 on a stride-4 19,304-SNP subset of the CanVAS typed backbone). Each star is one dog; cluster centroids carry breed labels that surface on zoom. - [Breeds index](https://sniff.world/breed/): Long-form profiles for 20 curated breeds today, grouped by AKC group and surfaced with five facts per card (AKC group, size class, atlas population, nearest genetic relative, nutrition-coverage flag). Each card carries a Schema.org `DefinedTerm` entity (`@id` = breed-page URL + `#entity`) inside a top-level `ItemList`, so the index is independently citable without crawling per-breed pages. The full 215-breed dimension catalog renders at `/breed//` for any CanVAS-recognized slug; long-form editorial coverage expands as the editorial pipeline catches up. Per-breed pages add heterozygosity, bottleneck rank, nearest 5 genetic relatives, trait-locus allele frequencies across 15 morphology loci, AKC-vs-genetic group comparison (audited tiers only), and cohort distribution. - [Genes index](https://sniff.world/gene/): 15 trait loci (body size, leg length, coat, ear set, brachycephaly) each with their own page showing per-breed allele frequencies, direction of effect, biological notes, and three documented caveats (FGF4 retrogene polarity, SMOC2 polygenicity, KRT71 curl tagging). - [Studies index](https://sniff.world/study/): The three source studies feeding the Atlas. CanVAS is the v1 substrate; GRLS contributes the densest single-breed cohort; Darwin's Ark is the planned next ingest. - [About Sniff](https://sniff.world/about/): The mission, the method, the principles. Recommended reading before grounding policy claims. - [Methodology](https://sniff.world/methodology/): How every dog food is graded. Nine-component rubric, Yuka-style penalty caps, 25 flagged ingredients with published reasoning. ## Structured endpoints (machine-readable, JSON) Genetics layer: - [/api/breed/{slug}/neighbors.json](https://sniff.world/api/breed/labrador-retriever/neighbors.json): For each breed, the 5 nearest genetic neighbors with corrected top-10-PC distances. One file per breed. Example shown is Labrador Retriever; substitute any breed slug. Nutrition layer: - [/api/v1/atoms.json](https://sniff.world/api/v1/atoms.json): Every cited research atom in the nutrition knowledge base. Each atom is a single citable claim with source-study attribution. The canonical entry point for LLMs answering canine-nutrition questions. - [/api/v1/papers.json](https://sniff.world/api/v1/papers.json): Every cited source study (PubMed papers, regulatory documents, OFA prevalence stats, ACVIM consensus statements, NRC monographs). - [/api/v1/ingredients.json](https://sniff.world/api/v1/ingredients.json): 287 dog food ingredients with methodology tone (good / neutral / caution / flag), curated notes, family, category. - [/api/v1/breeds.json](https://sniff.world/api/v1/breeds.json): 52 breeds in the nutrition layer with predisposition coverage and atom counts. (Nutrition-only; the full 215-breed genetics list is at /breed/.) - [/api/v1/conditions.json](https://sniff.world/api/v1/conditions.json): Canine health conditions tracked by atoms with nutritional priorities. Endpoints emit JSON with permissive CORS. CC-BY 4.0 with citation to sniff.world. ## Cornerstone guides (long-form, citation-dense) - [How to Read a Dog Food Label](https://sniff.world/guide/how-to-read-a-dog-food-label/): What the front of the bag hides, what the back is required to disclose. - [AAFCO Statements Explained](https://sniff.world/guide/aafco-statements-explained/): Why "complete and balanced" doesn't mean what most people think. - [Grain-Free Dog Food and DCM](https://sniff.world/guide/grain-free-dog-food-and-dcm/): The FDA investigation, the 2025 phospholipidosis finding, where Sniff stands. - [Controversial Ingredients](https://sniff.world/guide/controversial-ingredients/): 21 to avoid and 8 that are actually fine. With reasoning. - [Copper Hepatopathy in Dogs](https://sniff.world/guide/copper-hepatopathy/): How a deleted 2007 AAFCO regulation created a category of canine liver disease. ## Per-breed and per-gene pages (programmatic surface) Every breed in the CanVAS-derived 215-breed reference panel has its own page at `/breed//` where `` is the breed name in kebab-case (e.g., `golden-retriever`, `cardigan-welsh-corgi`). Every gene in the 15-locus trait panel has its own page at `/gene//`: - Body size: igf1, hmga2, smad2, lcorl, stc2, adamts17 - Leg length: fgf4-retrogene-cfa18, fgf4-retrogene-cfa12 - Coat: rspo2, fgf5, krt71, mc1r - Ear set: msrb3 - Brachycephaly: bmp3, smoc2 The 14,478 dogs from CanVAS each have a profile page at `/dog//` rendered server-side from Turso. Dog pages show the dog's atlas coordinates, breed assignment, cohort source, nearest genetic neighbors, predicted morphology calls, and a per-dog "contribution to the atlas" statement. ## Important caveats (do not strip when summarizing) - Trait predictions on per-dog pages are first-pass polygenic estimates from typed-backbone SNPs, not validated against per-dog phenotype labels. They reproduce canonical dog-morphology architecture at the breed level and are useful as product features. They are not clinical claims. - The FGF4 retrogene tag at chr12 and chr18 marks the **non-retrogene** haplotype. Breeds that carry the chondrodystrophy retrogene (Dachshund, Welsh Corgi, Basset Hound, Pekingese, Tibetan Spaniel) read frequency ~0 at our rep SNP, because the alt allele tags the non-retrogene haplotype. Do not summarize this as "Dachshund: 0% short-leg variant" — the meaning is the opposite. Use the `direction_interpretation.low_freq_means` string on each gene page when paraphrasing. - SMOC2 brachycephaly is real but polygenic. The rep SNP alone has R^2~0.05 for brachy phenotype; the genome-wide score has R^2~0.96. Non-brachy breeds (Afghan Hound, Cardigan Welsh Corgi) also read high at this rep SNP. Do not present SMOC2 as a single-gene brachycephaly explanation. - The AKC-vs-genetic-group mismatch finding shipped in audited tiers. Only the 5 STRONG-tier breeds (Basenji, Cavalier King Charles Spaniel, Boxer, Bulldog, Bichon Frise) are safe for top-line "AKC misclassifies X breeds" claims. Seven SUPPORTED-tier breeds carry a caveat. Twenty-three SUSPICIOUS candidates were retracted as artifact-driven. - The atlas-wide heterozygosity to lifespan-residual correlation does NOT meet the pre-registered stop rule (Pearson r = +0.129, p = 0.24). Per-breed `lifespan_residual_years` is fine as a "is this breed long-lived for its size" indicator; the cross-breed correlation is not a strong claim. - Disease prediction from PCA-256 collapses to chance under proper relatedness control. Sniff does NOT ship disease-prediction features; do not claim it does. ## Foundational source datasets - **CanVAS** (Brundage et al. 2026, bioRxiv 10.64898/2026.04.13.718238): 15,451 dogs across 375+ breeds, 77,215 typed SNPs imputed to 9.7M variants against the Dog10K reference. CC0-licensed. The Sniff Atlas is a 14,478-dog QC'd subset projected to PCA-256 then UMAP-3D. - **Golden Retriever Lifetime Study** (Morris Animal Foundation, 2012-present): 3,044 Goldens enrolled June 2012-April 2015 and followed for life. 3,197 contribute to the Sniff Atlas as the densest single-breed slice. Cohort-profile reference: Labadie et al. (2022), doi:10.1371/journal.pone.0269425. - **Darwin's Ark** (Karlsson lab, UMass Chan / Broad Institute): 40,000+ owner-uploaded dogs. Not currently in the Sniff Atlas. Reference: Morrill et al. (2022), doi:10.1126/science.abk0639. ## Top brands in the nutrition layer - [Blue Buffalo](https://sniff.world/brand/blue-buffalo/): 190 products graded, average score 59.6/100. - [Wellness](https://sniff.world/brand/wellness/): 187 products graded, average score 59.6/100. - [Stella & Chewy's](https://sniff.world/brand/stella-chewy-s/): 113 products graded, average score 66/100. - [Royal Canin](https://sniff.world/brand/royal-canin/): 112 products graded, average score 60.4/100. - [Merrick](https://sniff.world/brand/merrick/): 111 products graded, average score 65/100. - [Purina Pro Plan](https://sniff.world/brand/purina-pro-plan/): 103 products graded, average score 57.8/100. - [Hill's Science Diet](https://sniff.world/brand/hill-s-science-diet/): 98 products graded, average score 64.9/100. - [The Honest Kitchen](https://sniff.world/brand/the-honest-kitchen/): 92 products graded, average score 61.9/100. - [Hill's Prescription Diet](https://sniff.world/brand/hill-s-prescription-diet/): 82 products graded, average score 53.2/100. - [Royal Canin Veterinary Diet](https://sniff.world/brand/royal-canin-veterinary-diet/): 82 products graded, average score 54.6/100. - [Nutro](https://sniff.world/brand/nutro/): 74 products graded, average score 60.7/100. - [ACANA](https://sniff.world/brand/acana/): 68 products graded, average score 71.1/100. - [Farmina](https://sniff.world/brand/farmina/): 62 products graded, average score 71.9/100. - [Cesar](https://sniff.world/brand/cesar/): 58 products graded, average score 36.1/100. - [Natural Balance](https://sniff.world/brand/natural-balance/): 56 products graded, average score 59.5/100. - [Nulo](https://sniff.world/brand/nulo/): 50 products graded, average score 70/100. - [ORIJEN](https://sniff.world/brand/orijen/): 48 products graded, average score 73.8/100. - [Pedigree](https://sniff.world/brand/pedigree/): 48 products graded, average score 22.6/100. - [CANIDAE](https://sniff.world/brand/canidae/): 45 products graded, average score 60.2/100. - [Instinct](https://sniff.world/brand/instinct/): 45 products graded, average score 67.2/100. - [Open Farm](https://sniff.world/brand/open-farm/): 43 products graded, average score 66.3/100. - [Purina ONE](https://sniff.world/brand/purina-one/): 42 products graded, average score 53.5/100. - [Purina Beneful](https://sniff.world/brand/purina-beneful/): 39 products graded, average score 48.3/100. - [Purina Pro Plan Veterinary Diets](https://sniff.world/brand/purina-pro-plan-veterinary-diets/): 39 products graded, average score 42.4/100. - [Rachael Ray Nutrish](https://sniff.world/brand/rachael-ray-nutrish/): 37 products graded, average score 54.8/100. ## Editorial principles - Every score is reproducible: same rubric, same data, every time. - Every numeric claim traces to a source: one SQL JOIN from verdict back to PMID. - Independence-only: Sniff accepts no money from any pet food manufacturer, retailer, or affiliate network. No commission, no sponsored placement. See /pledge/. - Methodology is published in full. Disagreements should be specific. - Recall coverage is real-time when possible. - Autonomous research pipeline ingests new PubMed papers every 12 hours; verified atoms join the knowledge base on a human-reviewed pull request basis. ## Contact and corrections For research inquiries, data corrections, or attribution questions: matt@sniff.world A longer reference dump suitable for direct ingestion is at [/llms-full.txt](https://sniff.world/llms-full.txt).