与 “Thatcher”类似的 “RL6077” 基因型小麦被公认为携带有Lr34/Yr18基因，该基因赋予小麦抗叶锈病和条锈病的成株植物抗性 (APR)。然而，在RL6077全基因序列中使用分子标记却无法寻找到该基因。
国际玉米和小麦改良中心（CIMMYT）的Sybil A. Herrera-Foessel和其他科学家把RL6077与敏感型小麦“Avocet”杂交，从光敏感植株中分离获得叶锈病和条锈病抗性植株。此品种已在各个地点种植并接受抗性评估。结果表明，其确实与锈病响应相关，该基因或紧密连锁的基因能够抵抗上述两种锈病。通过分子定位，在4DL染色体上确定了五个分子标记。
与此同时，加拿大的研究者把Thatcher和RL6077杂交后，在相同的染色体区域发现同一个基因（Lr67），将其命名为Yr46，他们认为Lr67/Yr46可与其他抗锈病基因共同使用，起到小麦抗叶锈病和条锈病的补偿作用。（生物谷Bioon.com）
生物谷推荐英文摘要：
TAG Theoretical and Applied Genetics DOI: 10.1007/s00122-010-1439-x
New slow-rusting leaf rust and stripe rust resistance genes Lr67 and Yr46 in wheat are pleiotropic or closely linked
Sybil A. Herrera-Foessel, Evans S. Lagudah, Julio Huerta-Espino, Matthew J. Hayden, Harbans S. Bariana, Davinder Singh and Ravi P. Singh
The common wheat genotype ‘RL6077’ was believed to carry the gene Lr34/Yr18 that confers slow-rusting adult plant resistance (APR) to leaf rust and stripe rust but located to a different chromosome through inter-chromosomal reciprocal translocation. However, haplotyping using the cloned Lr34/Yr18 diagnostic marker and the complete sequencing of the gene indicated Lr34/Yr18 is absent in RL6077. We crossed RL6077 with the susceptible parent ‘Avocet’ and developed F3, F4 and F6 populations from photoperiod-insensitive F3 lines that were segregating for resistance to leaf rust and stripe rust. The populations were characterized for leaf rust resistance at two Mexican sites, Cd. Obregon during the 2008–2009 and 2009–2010 crop seasons, and El Batan during 2009, and for stripe rust resistance at Toluca, a third Mexican site, during 2009. The F3 population was also evaluated for stripe rust resistance at Cobbitty, Australia, during 2009. Most lines had correlated responses to leaf rust and stripe rust, indicating that either the same gene, or closely linked genes, confers resistance to both diseases. Molecular mapping using microsatellites led to the identification of five markers (Xgwm165, Xgwm192, Xcfd71, Xbarc98 and Xcfd23) on chromosome 4DL that are associated with this gene(s), with the closest markers being located at 0.4 cM. In a parallel study in Canada using a Thatcher × RL6077 F3 population, the same leaf rust resistance gene was designated as Lr67 and mapped to the same chromosomal region. The pleiotropic, or closely linked, gene derived from RL6077 that conferred stripe rust resistance in this study was designated as Yr46. The slow-rusting gene(s) Lr67/Yr46 can be utilized in combination with other slow-rusting genes to develop high levels of durable APR to leaf rust and stripe rust in wheat.
