What subclade are these halogroups? R1b1a1b1a1a1c2a1 and R1b1a1b1a1a2b2
Executive summary
Both strings—R1b1a1b1a1a1c2a1 and R1b1a1b1a1a2b2—appear to be deep downstream designations inside the R1b phylogeny that, on the basis of standard nomenclature in the supplied sources, sit under the major R1b-M269 branch (also written R1b1a1b) rather than outside it, but the provided reporting does not list those exact long alphanumeric labels so a definitive SNP-equivalent name cannot be confirmed from these sources alone [1] [2] [3].
1. What the labels most likely mean in broad terms
The R1b tree is conventionally expressed either as nested R1b1a1b-style clades or by specific SNP names such as R‑M269; multiple sources equate R1b1a1b with the M269 lineage that dominates Western Europe, and therefore any label that begins R1b1a1b… is, in broad classification, part of that R‑M269 branch unless shown otherwise by SNP data [1] [2].
2. Why a precise SNP name matters — and why the sources stop short
Authoritative genealogy resources emphasize that the short “R1b…” strings are phylogenetic placeholders while researchers and testers prefer SNP labels (e.g., M269, L21, U106) because they map to tested mutations; ISOGG and testing services recommend targeted SNP testing to move from a predicted R1b sub-branch into a confirmed SNP-defined subclade, which means published wiki pages and project trees will show many common SNP equivalents but may not include every deeply nested alphanumeric label encountered in user outputs [2] [4].
3. Examples of how the two naming systems map in practice
Wikipedia and ISOGG illustrate the mapping practice: R1b1a1b is equated with R‑M269 in current schemes and downstream major lineages of R‑M269 are commonly named by their SNPs (for example L21/DF13 in the L21 branch), showing that the readable SNP labels are the convention used by the literature and projects to communicate subclade identity [1] [5].
4. The practical implication for the two specific strings given
Given the absence of these exact labels in the provided sources, the responsible conclusion from the reporting is that both R1b1a1b1a1a1c2a1 and R1b1a1b1a1a2b2 are almost certainly downstream sub-branches of R1b1a1b (R‑M269) based on their prefix, but neither Wikipedia, ISOGG nor the project pages in the search results supply a direct SNP-equivalent mapping for those particular long branch names, so the sources do not permit a firm one-to-one identification to an SNP like U106, P312, L21 or DF27 without additional, up-to-date tree data or direct SNP test results [1] [2] [4].
5. How to get a definitive answer and why different outlets may disagree
FamilyTreeDNA and R1b projects routinely place members into fine-grained subgroupings and advise ordering single-SNP tests or using full Y-sequence panels to confirm downstream placement—this is the practical route to convert an alphanumeric phylogenetic path into a standard SNP name that the literature recognizes; alternative online write-ups (Eupedia, project pages, family blogs) can offer likely placements but vary in completeness and sometimes use older nomenclature, so they should be treated as suggestive rather than definitive [6] [7] [8].
6. Caveats, alternate viewpoints and reporting limits
The reporting shows consensus on the major backbone (R1b → R‑M269 → many SNP-defined subclades) but does not catalogue every modern downstream label; therefore it is possible that the two strings correspond to recognized SNP subclades in more current or specialized trees not captured in the supplied sources—honest reporting requires acknowledging that limitation and recommending direct SNP testing or consulting the latest ISOGG/FTDNA phylogeny for final conversion [1] [4] [2].