Introduction:
- Around 15% of malignancies, 50% of mental retardation, 50% of congenital abnormalities, 50% of miscarriages, and 50% of blindness are caused by genetics.
- Pregnant women of 35 years or more are candidates for prenatal diagnosis as risk of aneuploidy is higher in women of age 35 or more. There are various types of prenatal diagnosis which are offered during the different gestational age. However, the choice and selection of specific tests is fully dependent upon the respective mother, family, health care providers, and the clinical condition of the pregnant women. Moreover, every prenatal testing possesses it limitations and however, it will aid in making decisions about their care to partner with patients and families
- Maternal serum marker screening tests, Chorionic Villus Sampling (CVS), and amniocentesis are some of the prenatal testing.
- Prenatal diagnosis of neural tube defects is not possible by chorionic villus sampling (CVS). Muscle dystrophy cannot be diagnosed by CVS or amniocentesis. Muscle biopsy is diagnostic.
- Prenatal diagnosis of hemophilia is based on linkage analysis. Genetic linkage analysis can be performed by RFLP.
Prenatal diagnosis for genetic disorders:
Several single gene disorders are diagnosed by DNA analysis
Alzheimer’s disease (AD) disorders
- Huntington’s disease
- Myotonic dystrophy
- Neurofibromatosis
Autosomal recessive (AR) disorders
- Sickle cell Anaemia
- Cystic fibrosis
- Thalassemia alpha and Beta
- Tay Sachs disease
- Phenylketonuria (PKU)
X-linked disorders
- Haemophilia A and B
- Duchenne Muscular Dystrophy (DMD)