Lowe A J, Moule C, Trick M, Edwards K J
IACR Long Ashton Research Station, Long Ashton, BS41 9AF, Bristol, UK.
Theor Appl Genet. 2004 Apr;108(6):1103-12. doi: 10.1007/s00122-003-1522-7. Epub 2003 Dec 5.
A set of 398 simple sequence repeat markers (SSRs) have been developed and characterised for use with genetic studies of Brassica species. Small-insert (250-900 bp) genomic libraries from Brassica rapa, B. nigra, B. oleracea and B. napus, highly enriched for dinucleotide and trinucleotide SSR motifs, were constructed. Screening the clones with a mixture of oligonucleotide repeat probes revealed positive hybridisation to between 75% and 90% of the clones. Of these, 1230 were sequenced. Primer pairs were designed for 398 SSR clones, and of these, 270 (67.8%) amplified a PCR product of the expected size in their focal and/or closely related species. A further screen of 138 primers pairs that produced a PCR product in B. napus germplasm found that 86 (62.3%) revealed length polymorphisms within at least one line of a test array representing the four Brassica species. The results of this screen were used to identify 56 SSRs and were combined with 41 SSRs that had previously shown polymorphism between the parents of a B. napus mapping population. These 97 SSR markers were mapped relative to a framework of RFLP markers and detected 136 loci over all 19 linkage groups of the oilseed rape genome.
已经开发并鉴定了一组398个简单序列重复标记（SSR），用于芸苔属物种的遗传研究。构建了来自白菜型油菜、黑芥、甘蓝和甘蓝型油菜的小插入片段（250 - 900 bp）基因组文库，这些文库高度富集二核苷酸和三核苷酸SSR基序。用寡核苷酸重复探针混合物筛选克隆，结果显示75%至90%的克隆出现阳性杂交。其中，1230个进行了测序。为398个SSR克隆设计了引物对，其中270个（67.8%）在其目标物种和/或近缘物种中扩增出预期大小的PCR产物。对在甘蓝型油菜种质中产生PCR产物的138对引物进行进一步筛选，发现86对（62.3%）在代表四种芸苔属物种的测试阵列的至少一个品系中显示出长度多态性。该筛选结果用于鉴定56个SSR，并与之前在甘蓝型油菜作图群体的亲本之间显示多态性的41个SSR相结合。这97个SSR标记相对于RFLP标记框架进行定位，并在油菜基因组的所有19个连锁群上检测到136个位点。
