The technical advances in molecular biology have endowed us with a wealth of knowledge, which has allowed us to identify the cause of diseases not only at a single gene level but at a greater magnitude, where a substitution or deletion of a single base pair can be identified. Our present task is to establish a clear link between phenotype and nucleotide sequence. Obviously, a gene is no longer an imaginary entity. Recent discoveries in a number of bewildering traits, whose inheritance do not follow simple mendelian rules, have caused much amazement. For example, fragile X-syndrome, spine and bulbar muscular atrophy and myotic dystrophy arise from "triples repeat mutation" and amplification in future generations. Genetic diseases which are inherited, can now be diagnosed prenatally; an idea that was once inconceivable.
The aim of the second volume, entitled Morbid Anatomy of the Genome, is to reflect on the importance of molecular genetics in modern medicine. The field has expanded so as to warrant a volume dedicated exclusively toward understanding those who wish to know the cause, detection and in turn treatment of such diseases. In this volume, I have commissioned several scientists to contribute 12 chapters. A chapter describing a special role of molecular genetics in combating genetic diseases through gene therapy has also been included, while chapter 13 is a commentary.
A complete account of all diseases whose genetic basis is well established would be a herculean task and is not within the scope of a single volume format. Therefore a few specific topics have been chosen which may be of the greatest interest to scientists and clinicians. The purpose of this issue is to keep abreast of the latest developments in a select group of genetic diseases.

The laws of inheritance were considered quite superficial until 1903, when the chromosome theory of heredity was established by Sutton and Boveri. The discovery of the double helix and the genetic code led to our understanding of gene structure and function. For the past quarter of a century, remarkable progress has been made in the characterization of the human genome in order to search for coherent views of genes. The unit of inheritance termed factor or gene, once upon a time thought to be a trivial an imaginary entity, is now perceived clearly as the precise unit of inheritance that has continually deluged us with amazement by its complex identity and behaviour, sometimes bypassing the university of Mendel's law.
The aim of the fifth volume, entitled Genes and Genomes, is to cover the topics ranging from the structure of DNA itself to the structure of the complete genome, along with everything in between, encompassing 12 chapters. These chapters relate much of the information accumulated on the role of DNA in the organization of genes and genomes per se. Several distinguished scientists, all pre-eminent authorities in each field to share their expertise. Obviously, since the historical report on the double helix configuration in 1953, voluminous reports on the meteoric advances in genetics have been accumulated, and to cover every account in a single volume format would be a Herculean task. Therefore, only a few topics are chosen, which are of great interest to molecular geneticists. This volume is intended for advanced graduate students who would wish to keep abreast with the most recent trends in genome biology.

The underlying idea that cancer is a genetic disease at the cellular level was postulated over 75 years ago when Boveri hypothesised that the malignant cell was one that had obtained an abnormal chromatin content. However, it has been only the last decade where enormous strides have been made toward understanding neoplastic development. Explosive growth in the discipline of cancer genetics is so rapid that any attempt to review this subject becomes rapidly outdated and continuous revisions are warranted. Conclusive evidence has been reached associating specific chromosomal abnormalities to various cancers. We have just begun to characterise the genes, which are involved in these consistent chromosomal rearrangements resulting in the elucidation of the mechanisms of neoplastic transformation at a molecular level. The identification of over 50 oncogenes has led to a better understanding of the physiological process. Tumor suppresser genes, which were discovered through inheritance mechanisms, have further shed some light towards understanding the loss of heterozygosity during carcinogenesis. The message emerging with increasing clarity concerning specific pathways which regulate the fundamental process of cell division and uncontrolled growth.
The advances in molecular biology have led to a major insight in establishing precise diagnosis and treatment of many cancers resulting in prevention of death. The field is expanding so rapidly that a complete account of all aspects of genetics of cancer could not be accommodated within the scope of a single volume format. Nevertheless, a few very specific topics have been chosen, which readers may find of great interest in hopes that their interest may be rejuvenated concerning the bewildering nature of this deadly disease. The contributors to Volume 3 have provided up-to-date accounts of their fields of expertise. Although the contributors have kept their chapters brief, they include an extensive bibliography for those who wish to understand a particular topic in depth.
For more than a century, cancer has been diagnosed on the enigmatic basis of morphological features. Establishing a diagnosis based on DNA, RNA, and proteins, which is done routinely now, was once inconceivable. Cloning a gene of hematopoietic origin is no longer a fantasy. The approach has shifted over the past 15 years from identification of chromosomal abnormalities toward zeroing in on cancer genes.

The Genetical Theory of Natural Selection by R.A. Fisher (1930) dictated that sexual dimorphisms may depend upon a single medelian factor. This could be true for some species but his suggestion could not take off the ground as gender in Drosophila is determined by the number of X chromosomes. Technical advances in molecular biology have revived the initial thinking of Fisher and dictate that TDF or SRY genes in humans or Tdy in mice are sex determining genes. The fortuitous findings of XX males and XY female, which are generally termed sex reversal phenomenon, are quite bewildering traits that have caused much amazement concerning the pairing mechanism(s) of the pseudoautosomal regions of human X and Y chromosomes at meiosis. These findings have opened new avenues to explore further the genetic basis of sex determination at the single gene level.
The aim of the fourth volume, titled Genetics of Sex Determination is to reflect on the latest advances and future investigative directions, encompassing 10 chapters. Commissioned several distinguished scientists, all pre-eminent authorities in each field to shed their thoughts concisely but epitomise their chapters with an extended bibliography. Obviously, during the past 60 years, the metoric advances are voluminous and to cover every account of genes, chromosomes, and sex in a single volume format would be a herculean task. Therefore, a few specific topics are chosen, which may be of great interest to scientists and clinicians. The seasoned scientists who love to inquire about the role of genes in sex determination should find the original work of these notable contributors very enlightening. This volume is intended for advanced students who want to keep abreast as well as for those who indulge in the search for genes of sex determination.

Medical students often feel they understand the theory behind the clinical aspect of medicine but seldom have enough chance to put what they learn into practice. In addition, clinical examinations pose a challenge to students who may be technically and theoretically excellent, but who have poor examination technique. It is quite common for students to lack understanding of how they will be marked, how much emphasis to place upon certain actions or how much detail is expected of them. 'OSCE CASES WITH MARK SCHEMES' is intended to fill this gap. It provides OSCE mark schemes to reflect the real OSCE experience, by encouraging self assessment when practicing the clinical scenarios. The book includes chapters on communication skills, medical ethics, explanation stations, paediatrics and obstetrics and gynaecology subjects which are sometimes neglected elsewhere. All four authors have taken part in medical student teaching and OSCE examinations. They understand what will earn marks in the actual exam. All the OSCE scenarios are from stations previously examined in the UK's top medical schools. This book prepares the student for what the actual finals exam will be like. CONTENTS: SECTION ONE, COMMUNICATION STATIONS - Presenting Complaints - Psychiatry History Taking - Pediatrics History Taking - Obstetrics History Taking - Gynaecology History Taking - Medical Ethics - Difficult Communication Scenarios - Pharmacology - Consenting - Explanation of Management and Results SECTION TWO, PERFORMANCE STATIONS - Examination Skills - Practical Skills - Data Interpretation - Closing Remarks