Genetic and physical mapping of homoeologous recombination points involving wheat chromosome 2B and rye chromosome 2R
Bibliographic record
Abstract
Wide hybrids have been used in generating genetic maps of many plant species. In this study, genetic and physical mapping was performed on ph1b-induced recombinants of rye chromosome 2R in wheat (Triticum aestivum L.). All recombinants were single breakpoint translocations. Recombination 2RS-2BS was absent from the terminal and the pericentric regions and was distributed randomly along an intercalary segment covering approximately 65% of the arm's length. Such a distribution probably resulted from structural differences at the telomeres of 2RS and wheat 2BS arm that disrupted telomeric initiation of pairing. Recombination 2RL-2BL was confined to the terminal 25% of the arm's length. A genetic map of homoeologous recombination 2R-2B was generated using relative recombination frequencies and aligned with maps of chromosomes 2B and 2R based on homologous recombination. The alignment of the short arms showed a shift of homoeologous recombination toward the centromere. On the long arms, the distribution of homoeologous recombination was the same as that of homologous recombination in the distal halves of the maps, but the absence of multiple crossovers in homoeologous recombination eliminated the proximal half of the map. The results confirm that homoeologous recombination in wheat is based on single exchanges per arm, indicate that the distribution of these single homoeologous exchanges is similar to the distribution of the first (distal) crossovers in homologues, and suggest that successive crossovers in an arm generate specific portions of genetic maps. A difference in the distribution of recombination between the short and long arms indicates that the distal crossover localization in wheat is not dictated by a restricted distribution of DNA sequences capable of recombination but by the pattern of pairing initiation, and that can be affected by structural differences. Restriction of homoeologous recombination to single crossovers in the distal part of the genetic map complicates chromosome engineering efforts targeting genes in the proximal map regions.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".