Basics of Medical Genetics - Buzhiyevska T.I. 2001

Introduction

Life on Earth is built upon a unified design, driven by common mechanisms and laws that ensure the encoding of an individual's life program, the transmission of this code to offspring, the execution of this program in specific conditions (across space and time), and the modification and adjustment of this program—without which evolution itself would be impossible. The science that studies the heredity and Variability of organisms is called genetics. This biological discipline pursues two primary goals: 1. To study the patterns of heredity and variability. 2. To apply the acquired scientific knowledge in human practical activity.

Anyone who has chosen medicine as their profession must undoubtedly master General Genetics, Human Genetics, medical genetics, and the diagnostic capabilities of clinical-genealogical analysis, molecular and biochemical genetics, and cytogenetics. Physicians of all specialties must grasp the fundamentals of emerging scientific fields such as Population Genetics, immunogenetics, Pharmacogenetics, and oncogenetics, and understand the possibilities and principles of Medical and Genetic family counseling. Without this foundation, a physician cannot think genetically and thus evaluates normality and pathology, health and disease, solely through the lens of harmful environmental factors (infectious agents, nutritional deficiencies, trauma, toxins, radiation, etc.) affecting some Abstract "average" person. Such a perspective is akin to viewing a flat image with one eye instead of perceiving three-dimensional reality, which can only be comprehended with both.

Today, at the close of the 20th century, and all the more so for the physicians of the next era, such a limited view is not only insufficient but fundamentally flawed. There is no such thing as an "average" person in medicine; there is only a specific individual of a certain sex and age, possessing a unique, peerless genetic program that determines their personal reaction norm to environmental factors. No two identical people exist (with the exception of monozygotic twins). In humans, as in every living creature, all information regarding physical and biological traits, environmental sensitivity, predisposition to specific mental or other activities, behavior, the speed and strength of reactions to external and internal stimuli, food or drug intolerances, hypersensitivity to infections and radiation, and susceptibility to diseases of various Organs and systems, Metabolic Disorders, neuropsychiatric conditions, and oncopathology is inscribed in the genetic material of every Cell in The Human Body. Yet all these Cells are descendants of a single zygote—an egg cell fertilized by a sperm. In other words, the human Organism is a clone. At the moment of Fertilization, parental Genetic information unites, and the program coded in space and time begins to unfold. Prior to fertilization, the information within the Germ Cells is dormant, their hereditary material containing compressed space and time. During sexual reproduction, the fusion of male and female Gametes serves as point zero (the "start" signal), initiating the unfolding of the organism's life program from the Embryonic Stage through childhood, Puberty, reproductive age, senescence, disease, and death. Medical genetics is of paramount importance to obstetricians-gynecologists and pediatricians, who are the first to encounter the consequences of a particular genetic program's execution and are positioned to create individualized conditions for this process, taking into account its unique features in every case. The proper utilization of these opportunities will help safeguard the organism's future health, ensure reproductive success, prevent disability and premature death, and lay the groundwork for the full expression of each personality and the extension of a fulfilling human life. Without a knowledge of genetics, it is impossible to treat the patient (rather than the disease), nor is it possible to competently and effectively prevent illnesses by creating an adaptive living environment for every individual. Genetics is not only the foundation of biology, but also the philosophy of life in general and of medicine in particular.