Review Article

SERUM BIOMARKERS IN EVALUATION AND VALIDATION OF DISEASES

H.D. Khanna

Abstract: Biomarkers are key molecular or cellular events that link a specific environmental exposure to a health outcome. Biomarkers play an important role in understanding the relationships between exposure to environmental chemicals, the development of chronic human diseases, and the identification of subgroups that are at increased risk for disease. The validation of biomarkers as early predictors of clinical disease can enhance health risk assessment and contribute to effective new disease prevention policies in environmental and occupational settings. The process of validating biomarkers involves dealing with a range of characteristics that include the intrinsic qualities of the biomarker, its determinants, and the analytic procedure. The principal goal is to discover biomarkers, with the ultimate objective of identifying differentially expressed proteins between diseased and healthy controls. Novel and fast high-throughput systems dramatically enhance the analysis of thousands of proteins and genes with very low volumes. It is becoming clear that the consideration of a single biomarker might not be potent enough to improve diagnostic specificity. Thus, it is essential to develop methods to measure several biomarkers together in a single well or on a biochip to create an accurate prognostic profile. Plasma/serum measurements are the gold standard in clinics, because they are minimally invasive and can be easily collected and processed. Plasma/serum data reflect a broad spectrum of changes. A major advantage of blood samples is that patients can be followed up and screened over several years. 

Review Article

BIOMARKERS GENESIS AND THEIR PERSPECTIVES

R.K. Saxena and D.V. Rai

Abstract: Biomarkers are an index develops in living systems before/during pathophysiological situations. Their elevation or reduction can provide the status of diseases and can help in the development of therapeutics for ailment at initial level for the alleviation of etiology of disease. A particular type of the physical characteristics generated in living system can be used to measure or indicate the etiopathological nature of development, effects or progress of a disease, illness or abnormal or pathological conditions. A distinct types of biochemical, genetic or molecular characteristic or substance or indices i.e. an indicator of a particular biological condition or process. Disease biomarkers have been used in several clinical areas, including oncology, metabolic disorders, neurological disease and immune systems malfunctioning. In recent years because of the progress of analysis technology (Biomarker system) several new biomarkers continue to be devised and used as diagnostic, predictive, prognostic, and toxic marker. In drug development area, biomarkers are used as surrogate endpoint to substitute for a clinical endpoint and needed for rational drug development.

Review Article

PHYSICAL MAPPING OF GENOME AND GENES

Rekha Dixit, Jayanand, DV Rai, Rashi Agarwal, Aditya Pundhir

Abstract: Mapping genome of an organism is an important tool to provide a guide for the sequencing experiments by showing the exact positions of genes and other distinctive features in the chromosomal DNA. Whole genome sequencing of eukaryotic genomes is greatly facilitated by high- density genome maps. The highdensity maps serve as foundation during organizing and assembling the nucleotide sequences of genomes. Reference to the map ensures that regions containing repetitive DNA are assembled correctly. Distinctive
features on the genome map are used as landmarks to aid assembly of master sequence from huge number of short sequences obtained from genomic library. First step for manipulation of genes for various applications is cloning that relies on mapping close to a convenient marker. A complete physical-genetic map of genome is necessary for comparative genomics studies with other genomes. High-resolution comparative physical maps will reveal regions of colinearity and rearrangement and will have important
implications for phylogenetic studies and genome evolution.