Monozygotic twins affected with major depressive disorder have greater variance in methylation than their unaffected co-twin

Our understanding of major depressive disorder (MDD) has focused on the influence of genetic variation and environmental risk factors. Growing evidence suggests the additional role of epigenetic mechanisms influencing susceptibility for complex traits. DNA sequence within discordant monozygotic twin (MZT) pairs is virtually identical; thus, they represent a powerful design for studying the contribution of epigenetic factors to disease liability. The aim of this study was to investigate whether specific methylation profiles in white blood cells could contribute to the aetiology of MDD. Participants were drawn from the Queensland Twin Registry and comprised 12 MZT pairs discordant for MDD and 12 MZT pairs concordant for no MDD and low neuroticism. Bisulphite treatment and genome-wide interrogation of differentially methylated CpG sites using the Illumina Human Methylation 450 BeadChip were performed in WBC-derived DNA. No overall difference in mean global methylation between cases and their unaffected co-twins was found; however, the differences in females was significant (P=0.005). The difference in variance across all probes between affected and unaffected twins was highly significant (P<2.2 × 10⁻¹⁶), with 52.4% of probes having higher variance in cases (binomial P-value<2.2 × 10⁻¹⁶). No significant differences in methylation were observed between discordant MZT pairs and their matched concordant MZT (permutation minimum P=0.11) at any individual probe. Larger samples are likely to be needed to identify true associations between methylation differences at specific CpG sites.     

Characterisation of microsatellite markers for the granite endemic Kunzea pulchella (Lindl.) A. S. George (Myrtaceae) identified using next generation sequencing

A set of 11 polymorphic microsatellite loci were developed for Kunzea pulchella, a plant species endemic to granite outcrops in Western Australia. Genomic sequences were obtained from next generation (454) sequencing. A total of 20 microsatellite markers were then chosen for amplification and genotyping trials in individuals across the species range. Eleven of these loci were selected for analysis based on amplification and genotyping success. All were polymorphic with 4–10 alleles per locus (mean = 5.9). Expected and observed heterozygosity ranged from 0.29 to 0.92 averaging 0.606 and 0.690 respectively. Loci were in Hardy–Weinberg equilibrium (P < 0.05) except for two which showed evidence for null alleles. Linkage disequilibrium was evident in three loci pair combinations. These polymorphic microsatellite markers will be valuable for analysis of population genetic structure and connectivity in K. pulchella.     

Isolation and characterisation of ten microsatellite markers for the tetraploid Stypandra glauca R.Br. (Hemerocallidaceae) identified using next generation sequencing

Ten polymorphic microsatellite loci were developed for the tetraploid plant species Stypandra glauca which is common on granite outcrops in Western Australia. Amplification and genotyping trials were conducted on 48 individuals from two sampling localities. All 10 loci revealed multi-banding patterns with up to 4 bands visible in individuals consistent with tetraploidy. The number of alleles per locus ranged from 6 to 32 (mean = 12.5). The proportion of observed heterozygotes at each locus ranged from 0.32 to 0.98 (mean = 0.73). These polymorphic microsatellite markers will facilitate further analysis of population genetic structure and connectivity in Stypandra glauca.     

Anxiety disorders are associated with verbal memory impairment in patients with Parkinson’s disease without dementia

Journal of Neurology - Preliminary evidence has demonstrated a link between anxiety and memory impairment in Parkinson’s disease (PD). This study further investigated this association using...     

Recent advances in optical diagnosis of oral cancers: Review and future perspectives

Optical diagnosis techniques offer several advantages over traditional approaches, including objectivity, speed, and cost, and these label‐free, noninvasive methods have the potential to change the future workflow of cancer management. The oral cavity is particularly accessible and, thus, such methods may serve as alternate/adjunct tools to traditional methods. Recently, in vivo human clinical studies have been initiated with a view to clinical translation of such technologies. A comprehensive review of optical methods in oral cancer diagnosis is presented. After an introduction to the epidemiology and etiological factors associated with oral cancers currently used, diagnostic methods and their limitations are presented. A thorough review of fluorescence, infrared absorption, and Raman spectroscopic methods in oral cancer diagnosis is presented. The applicability of minimally invasive methods based on serum/saliva is also discussed. The review concludes with a discussion on future demands and scope of developments from a clinical point of view. © 2015 Wiley Periodicals, Inc. Head Neck 38 : E2403–E2411, 2016