ABSTRACT
A set of SSR and RFLP markers for safflower (Carthamus tinctorius) and jeweled distaff thistle (C. oxyacanthus) was generated from cDNA and genomic libraries and by mining public and proprietary sequence databases. In total, 1412 PCR-based markers and 75 RFLP markers were screened and polymorphic loci were mapped in an intraspecific F2 population of C. tinctorius and an interspecific BC1 population of C. tinctorius x C. oxyacanthus. The two populations shared one common parent and the resulting linkage maps could be compared for synteny. The level of polymorphism was low in both populations and only 8.2% and 13.7% of the analyzed markers could be mapped in the intraspecific and interspecific maps, respectively. The two maps showed significant colinearity of markers in several regions and an apparent translocation or inversion event on one linkage group. Noticeable segregation distortion was found on one linkage group of the C. tinctorius map and dense clustering of loci occurred on several linkage groups of the C. oxyacanthus map. The two maps represent the first major linkage analysis of Carthamus species. The molecular tools will be useful for a variety of genetic and genomic applications in safflower and its related species and have been used in our laboratory to map a flower color gene in C. tinctorius.
Subject(s)
Carthamus/genetics , Chromosome Mapping/methods , Chromosomes, Plant/genetics , Minisatellite Repeats/genetics , Carthamus/classification , DNA, Plant/genetics , Gene Library , Genetic Markers/genetics , Hybridization, Genetic , Polymerase Chain Reaction , Polymorphism, Genetic , Polymorphism, Restriction Fragment Length , Species Specificity , SyntenyABSTRACT
The relationship between performance on information processing efficiency measures and MRI-derived lesion volume including global and regional T2 and T1 lesion volumes was investigated in 20 patients with relapsing-remitting multiple sclerosis (RRMS) and secondary progressive multiple sclerosis (SPMS). Processing speed, as measured by the Sternberg Memory Scanning Test, was significantly correlated with posterior fossa lesion volume and slowed reaction time in seven out of eight patients (six out of seven with SPMS) with any lesion volume in the posterior fossa suggesting a 'threshold effect'. Processing capacity as measured by the Salthouse Keeping Track Test was not significantly correlated with the MRI measures. Cognitive performance did not correlate with Expanded Disability Status Scale score, depression or fatigue, and patients performed within normal limits on tests of attention/concentration ability. The significant relationship between posterior fossa lesion volume and memory scanning speed in this study suggests that pathological damage in the posterior fossa may contribute to slowed cognitive processing and may be an important direction for future studies of cognitive function in multiple sclerosis. Lack of correlation of cognitive measures with the other MRI measures may be due to low lesion volume relative to other studies, sample composition, and limited pathological specificity of the MRI measures.
