Seed Dormancy Class and Ecophysiological Features of Veronicastrum sibiricum (L.) Pennell (Scrophulariaceae) Native to the Korea Peninsula.

Veronicastrum sibiricum is a perennial species distributed in Korea, Japan, Manchuria, China, and Siberia. This study aimed to determine the requirements for germination and dormancy break of V. sibiricum seeds and to classify the kind of seed dormancy. Additionally, its class of dormancy was compared with other Veronicastrum and Veronica species. V. sibiricum seeds were permeable to water and had a mature embryo during seed dispersal. In field conditions, germination was prevented by physiological dormancy, which was, however, relieved by March of the next year, allowing the start of germination when suitable environmental conditions occurred. In laboratory experiments, the seeds treated with 0, 2, 4, 8, and 12 weeks of cold stratification (4 °C) germinated to 0, 79, 75, 72, and 66%, respectively. After the GA3 treatment (2.887 mM), ≥90% of the seeds germinated during the four incubation weeks at 20/10 °C. Thus, 2.887 mM GA3 and at least two weeks at 4 °C were effective in breaking physiological dormancy and initiating germination. Therefore, the V. sibiricum seeds showed non-deep physiological dormancy (PD). Previous research, which determined seed dormancy classes, revealed that Veronica taxa have PD, morphological (MD), or morphophysiological seed dormancy (MPD). The differences in the seed dormancy classes in the Veronicastrum-Veronica clade suggested that seed dormancy traits had diverged. The results provide important data for the evolutionary ecological studies of seed dormancy and seed-based mass propagation of V. sibiricum.

DRD3 gene rs6280 polymorphism may be associated with alcohol dependence overall and with Lesch type I alcohol dependence in Koreans.

BACKGROUND: Several polymorphisms of the dopamine D3 receptor (DRD3) gene are reported to be involved in the susceptibility to alcoholism. Although the DRD3 rs6280 (Ser9Gly) polymorphism plays an important role in various psychiatric disorders, findings regarding the association between this single-nucleotide polymorphism (SNP) and alcohol dependence (AD) have been inconsistent. Therefore, the present study investigated the association between the DRD3 gene rs6280 polymorphism with AD and Lesch type I AD in Korean subjects. METHODS: The DRD3 rs6280 SNP was genotyped in a case-control sample comprising 245 AD patients and 130 healthy controls (HCs). Alcohol Use Disorders Identification Test (AUDIT) scores were also compared relative to genotype in all of the participants. RESULTS: This SNP was significantly associated with both AD overall (χ(2) = 10.09 and p = 0.001, and χ(2) = 10.60 and p = 0.005, for the recessive and additive models, respectively) and with Lesch type I AD (χ(2) = 11.70 and p = 0.001, and χ(2) = 11.70 and p = 0.003, for the recessive and additive models, respectively). The allele frequency differed significantly (χ(2) = 8.45, p = 0.004) between Lesch type I AD and HC subjects. The AUDIT total (F = 6.56, p = 0.011), hazardous alcohol use (F = 7.12, p = 0.008), dependence symptoms (F = 5.10, p = 0.025), and harmful alcohol use (F = 4.83, p = 0.029) scores were significantly higher in those who did not possess the S allele (genotype GG) than in those who did (genotypes SS ± SG). CONCLUSIONS: The findings of this study suggest that the DRD3 rs6280 polymorphism is associated with the development of both AD overall and Lesch type I AD in Koreans.

The association of DRD2 -141C and ANKK1 TaqIA polymorphisms with alcohol dependence in Korean population classified by the Lesch typology.

AIMS: Dopamine receptors are associated with reward and dependence towards alcohol. The polymorphisms of dopamine D2 receptor (DRD2) genes have been reported to be involved in susceptibility to alcoholism. Therefore, we investigated the association of three single-nucleotide polymorphisms (SNPs) in DRD2 and ankyrin repeat and kinase domain containing one (ANKK1) genes with alcohol dependence in Korean subjects, who were classified by the criteria of the Lesch typology. METHODS: The DRD2 -141C (Insertion (Ins)/Deletion (Del)), exon8 (A/G) and the ANKK1 TaqIA (A1/A2) polymorphisms were genotyped in a case-control sample consisting of 245 alcohol-dependent (AD) patients and 110 healthy controls. AD patients were classified into four subtypes by the Lesch typology. The majority of them (77.1%) were Lesch type 1. Differences in genotype and allele frequencies were examined between the AD patients and the controls. Also those analyses were done between the Lesch type 1 group and the controls. RESULTS: There were significant differences in the genotype and allele frequencies of -141C Ins/Del and TaqIA A1/A2 between the AD patients and the controls. However, there were no significant differences in genotype or allele frequencies of exon8 A/G between the AD patients and the controls. The -141C Ins/Ins and TaqIA A1+ variants were associated with Lesch type 1 AD patients. When analysing haplotypes of three SNPs, the odds ratio of -141C Ins-A-A1 was 2.286, while the odds ratio of -141C Del-G-A2 was 0.323. CONCLUSION: The present study showed a significant difference in DRD2 -141C and ANKK1 TaqIA polymorphisms between the AD patients and the controls. Our findings suggest that -141C Ins and TaqIA A1 alleles can be a predisposing factor for alcohol dependence in the Korean population.