Mental retardation or intellectual disability affects about 3% of the general population. One half of it is attributed to genetic factors and is therefore inheritable. Genetic basis of mental retardation is poorly understood. However information revealed from the human genome project has enabled to analyze the genetic determinants that have causative role in the onset of the disease. This book provides a compendium of basic information on the genetic factors that lead to this disability, methodology to screen the causative genetic defects and identification of new causative determinates. This information is critically important in the diagnosis and prognosis of mental retardation at an early stage, resulting in better management of the disease, ultimately leading to improvement in life of the affected individuals. The book offers a valuable source of information for the graduate and post graduate students in genetics, biology and medicine.

Bacillus thuringiensis cry proteins are effective in controlling harmful insects. However, the mechanism of Bt protein pesticidal action is not well understood. It is assumed that the pesticidal protein has affinity for specific receptors in the midgut of the susceptible larvae and binds irreversibly to create holes in the gut leading to eventual death of the target larvae. Main aim of the research is to identify, purify and characterize Bt delta endotoxin receptor in important pest American bollworm (Helicoverpa armigera). The study presented in this thesis is endeavored to; (1) discovery of a receptor protein, (2) purification of the receptor, (3)cloning of the newly discovered protein gene in E.coli, (4) expression studies on recombinant protein, (5) Complete sequencing of the cloned gene. The structural gene was cloned in expression vector. The cloned gene was sequenced and studied expression. The cloned, expressed, purified receptor protein was found to have characteristics of native protein of H.armigera. A new method for quick detection of Bt-receptor in crude BBMVs extract, was established.The sequence has novelty and Accession # A59445)or Q7M4K6.