Introduction
There has been remarkable progress in the field of genetics over recent years and applications of genetic concepts are increasingly shaping clinical practice by informing the way we investigate, counsel, and treat our patients.
Certain key milestones, such as the delineation of the human genome, have marked this progress as has the realization that the way genes function is far more complex than the information contained in the sequence of their DNA bases. The field of epigenetics is beginning to unravel the intricate ways in which gene function is influenced by factors external to the genes themselves.Obstetric and gynaecological practice has been greatly influenced by the fast-moving developments in genetics. This is not surprising considering how closely linked genetic concepts are with patterns of inheritance, fertility, the development and function of the fetoplacental unit, the effect of genetic conditions both on the developing fetus and the pregnant woman, and the approaches to prenatal and perinatal diagnosis. Genetics also influences the way gynaecological conditions are diagnosed and treated and has shed new light on the aetiology of many common gynaecological cancers as well as revealed new targets for therapeutic intervention.
This chapter provides an overview of basic concepts in genetics and the evolution of key laboratory techniques and genetic testing. It introduces genetic aspects of the clinical consultation and the principles underlying genetic counselling, as well as their application in the preconception and prenatal periods, and reviews the genetics of preimplantation and prenatal diagnosis. Finally, the way oncogenetics is shaping our understanding of common gynaecological cancers is reviewed. In many of the clinical scenarios outlined in the subsequent sections, close collaboration with clinical genetics colleagues is indicated.