Spectrum of genetic disorders and the impact on health care delivery: an introduction.

Until recently, infectious diseases and malnutrition-related disorders constituted the major cause of ill health and mortality in the world population. However, advances in treatment of such disorders and increased understanding of the molecular basis of heredity have led to genetically transmitted conditions becoming a major cause of morbidity and mortality. Several disorders, including chromosomal (Down syndrome, Turner syndrome), single-gene (sickle-cell disease, thalassaemia, glucose-6-phosphate dehydrogenase deficiency, haemophilia, inborn errors of metabolism) and multifactorial disorders (coronary artery disease, arteriosclerosis, diabetes mellitus, hypertension, obesity) are common and becoming increasingly important. As there is no agreed-upon definitive cure with acceptable risk, these disorders are a significant burden on the health care delivery system. This is because the chronic nature of genetic diseases requires lifelong medical attention, expensive supportive and symptomatic therapy and specialist care. This review outlines the genetic disorders, their impact on health care delivery systems and the general framework required to prevent and control these disorders.