Phenotypic and molecular screenings for determination of cassava mosaic disease (CMD) status in farmers' fields in Ebonyi State, Nigeria.

African cassava mosaic virus (ACMV) and East African cassava mosaic virus (EACMV) are among the major constraints to cassava productivity within tropical and sub-tropical regions, including Ebonyi State, Nigeria. Thus, virus indexing has become imperative to determine the status of cassava mosaic disease (CMD) in Ebonyi State, to implement appropriate preventive and control strategies. Seventy-eight cassava accessions obtained from different locations of Ebonyi State were phenotypically scored, using scales 1-5 depending on CMD symptomatic expressions, followed by multiplex-PCR and sequencing for validation. 11% of cassava accessions cultivated in Afikpo were resistant (RE) to ACMV compared to 8% of moderately-resistant (MR) accessions in Izzi and 55% of tolerant (TO) ACMV accessions in Ebonyi. 100% of cassava accessions in Onicha and 66% in Afikpo South were susceptible (SU) and highly susceptible (HS) to ACMV, respectively. With multiplex-PCR, 97.4% (ACMV) and 2.6% (EACMV) were positive. Dunn's multiple comparison tests of CMD mean incidence demonstrated differences (P < 0.05), except between RE and MR, and TO and MR. More transitions (A/G, C/T) compared to transversions (A/T, G/T), were detected, with nonsynonymous mutations (Leucine/Isoleucine; Valine/Isoleucine; Arginine/Lysine; Methionine/Isoleucine), and good bit-scores (91.13-99.07% identites; e-values of 7.00e-148-0.00e+00). Phylogeny resolved the sequences into five major groups. DNA sequencing validated the detected ACMV and EACMV species. This study revealed variants of ACMV and low adoption of RE and MR cassava accessions in the farmers' fields. The findings will guide in getting disease-free and resistant varieties as planting materials to significantly mitigate the CMD spread in Ebonyi State, Nigeria.

Understanding the Pathogenesis, Therapeutic Targets/Drug Action and Pharmacogenetics of Type 2 Diabetes: Is there a Future for Personalised Medicine?

Type 2 diabetes (T2D) is a chronic non-communicable disease that is of major health concern with a steadily rising prevalence across the globe. It is a metabolic disorder characterized by high blood glucose level either as a result of impaired insulin secretion and/or insulin action usually termed insulin resistance. This disease is influenced by lifestyle/feeding habit changes and genetic factors that cause physiological changes in glucose and lipid metabolism. As such, antidiabetic treatments have targeted specific enzymes, receptors, transport proteins, hormones, transcription factors, etc. that are related to glucose metabolism, fat metabolism, insulin secretion and insulin signalization. Genetic variations due to mutations in certain target genes have been shown to influence the pathogenesis of T2D but also these polymorphisms have been observed to alter the therapeutic efficacy of drugs as well as their safety. Pharmacogenetic studies have been able to identify specific genetic variants of target genes that affect the metabolism, therapeutic response and adverse effects of antidiabetic drugs with the aim to translate the research findings to clinical practice. However, pharmacogenetic studies have not fully been able to identify distinct genetic markers that can serve as biomarkers for genetic screening, thus, limiting personalised medicine. As we advocate personalised medicine for the management of T2D in the future, pharmacogenetic studies should lay emphasis on addressing challenges of genetic screening and its translation to personalised therapy.