Whole genome re-sequencing reveals the genetic diversity and evolutionary patterns of Eucommia ulmoides.

Eucommia ulmoides (E. ulmoides) is a deciduous perennial tree belonging to the order Garryales, and is known as "living fossil" plant, along with ginkgo (Ginkgo biloba), metaspaca (Metasequoia glyptostroboides) and dove tree (Davidia involucrata Baill). However, the genetic diversity and population structure of E. ulmoides are still  ambiguous nowdays. In this study, we re-sequenced the genomes of 12 E. ulmoides accessions from different major climatic geography regions in China to elucidate the genetic diversity, population structure and evolutionary pattern. By integration of phylogenetic analysis, principal component analysis and population structure analysis based on a number of high-quality SNPs, a total of 12 E. ulmoides accessions were clustered into four different groups. This result is consistent with their geographical location except for group samples from Shanghai and Hunan province. E. ulmoides accessions from Hunan province exhibited a closer genetic relationship with E. ulmoides accessions from Shanghai in China compared with other regions, which is also supported by the result of population structure analyses. Genetic diversity analysis further revealed that E. ulmoides samples in Shanghai and Hunan province were with higher genetic diversity than those in other regions in this study. In addition, we treated the E. ulmoides materials from Shanghai and Hunan province as group A, and the other materials from other places as group B, and then analyzed the evolutionary pattern of E. ulmoides. The result showed the significant differentiation (Fst = 0.1545) between group A and group B. Some candidate highly divergent genome regions were identified in group A by selective sweep analyses, and the function analysis of candidate genes in these regions showed that biological regulation processes could be correlated with the Eu-rubber biosynthesis. Notably, nine genes were identified from selective sweep regions. They were involved in the Eu-rubber biosynthesis and expressed in rubber containing tissues. The genetic diversity research and evolution model of E. ulmoides were preliminarily explored in this study, which laid the foundation for the protection of germplasm resources and the development and utilization of multipurpose germplasm resources in the future.

[A genetic study of 15 STR loci in Chinese East Mongolian population].

OBJECTIVE: To investigate the genetic polymorphisms of 15 STRs loci in Chinese East Mongolian population. METHODS: DNA samples from 105 unrelated individuals in Chinese East Mongolian population were screened by Power Plex 16 System and ABI3100 Genetic Analyzer. RESULTS: The genotype frequencies of these 15 STR loci meet the Hardy-Weinberg expectation. The Matching probability of 15 STRs loci were between 0.0084-0.2169, discriminating power (DP) at 0.7831-0.9916, heterozygosity (H) at 0.5619-0.9231, power of exclusion (PE) at 0.4490-0.8444, polymorphism information content (PIC) at 0.5438-0.9178. The total DP of 15 STRs loci is 0.9999999999998. CONCLUSION: Our results showed that the 15 STRs loci of Power Plex 16 System are valuable STR loci genetic marker system having high DP and are useful in forensic case work in Chinese East Mongolian population.