Clinical Presentation of Genetic Disorders in Patients Attending Genetic Outpatient Clinic of Assiut University Children Hospital

Overview

Genetic Epidemiology : is quickly expanding research field concerned with considerate the heritable aspect of disease risk, individual propensity to disease and eventually with contributing to a complete molecular understanding of pathogenesis. Genetics : is the scientific study of genes \&heredity of how certain qualities or traits are passed from parents to offspring as a result of changes in DNA sequence . A gene is a segment of DNA that contains instructions for building of one or more molecules Genetic disorders: is a health problem caused by one or more abnormalities in the genome. It can be caused by a mutation in a single gene (monogenic) or multiple genes (polygenic) or by a chromosomal abnormality. (1)mutations: affect the human genes either inherited from one or both parents or due to certain environmental factors Four of the main types include:(1)Single \_gene inheritance diseases :Single gene inheritance diseases are diseases that occur because one defective gene is present. They are known as monogenetic disorders.(EX:Marfan Syndrome ) (2)Multifactorial genetic inheritance disorders : Genetic disorders may also be complex, , meaning they are likely associated with the effects of multiple genes in combination with lifestyles and environmental factors. Multifactorial disorders include heart disease and diabetes. (3)chromosomal abnormalities : result from a problem with cell division and arise because of duplications or absences of entire chromosomes or pieces of chromosomes. Examples of chromosome abnormality disorders include(Down sydrome ) (4)Mitochondrial genetic inheritance disorders : are caused by mutations in the DNA of mitochondria, small particles within cell. Mitochondrial DNA is always inherited from the female parent since egg cells (unlike sperm cells) keep their mitochondrial DNA during the process of fertilization. Environmental Factors: called (mutagens)which can lead to genetic mutations Such as Chemical exposure , Radiation exposure , Smoking , UV rays exposure from the sun prognosis Of genetic disorders: Not all genetic disorders directly result in death, there are no known cures for genetic disorders. Many genetic disorders affect stages of development, such as Down syndrome, while others result in purely physical symptoms such as muscular dystrophy. Other disorders, such as Huntington's disease, show no signs until adulthood. .Treatment of genetic disorders: The treatment of genetic disorders is an ongoing battle, with over 1,800 gene therapy clinical trials having been completed, are ongoing, or have been approved worldwide, Despite this, most treatment options revolve around treating the symptoms of the disorders in an attempt to improve patient quality of life. Diagnosis of genetic disorders: (1)personal medical history :information about an individual health often going back to birth can provide clues to a genetic diagnosis (2)physical examination :certain physical characteristics , such as distinctive facial features can suggest the diagnosis of a genetic disorder , a geneticist will do a through physical Examination that may include measurements such as head circumference and so on . (3) Family health history :because genetic conditions often run in families , information about the health of family members can be a critical tool for diagnosing these disorders . (4)Laboratory Tests :including genetic testing , molecular , chromosomal , and biochemical genetic or genomic testing are used to diagnose genetic disorders. Genetic counselling is a communication process, which aims to help individuals, couples and families understand and adapt to the medical, psychological, familial and reproductive implications of the genetic contribution to specific health conditions. Patients With History Of TORCH: Bad Obstetric history (BOH) implies previous unfavorable foetal outcome in terms of two or more consecutive spontaneous abortion, history of intrauterine foetal death, intrauterine growth retardation, still births, early neonatal death and/or congenital anomalies. Cause of BOH may be genetic, hormonal, abnormal maternal immune response and maternal infection.