Genetic diseases are medical conditions that are the result of faulty or mutated genetic material. The diseases are impossible to cure at this time because the abnormal DNA is present in all of the cells in the body. Genetic diseases are usually hereditary, which means they can be passed on from generation to generation. Some genetic diseases require two mutated genes, which means an afflicted child can be born from two healthy parents.
Progeria
Progeria is a genetic disease that causes accelerated aging. As ProgeriaResearch.org explains, it affects one out of every 4 million to 8 million children and can affect both boys and girls. Children with progeria seem healthy at birth but begin to show signs of the disease between 18 and 24 months of age. Those symptoms include diminished growth, joint stiffness, skin that appears aged, atherosclerosis, and cardiovascular disease. Progeria is caused by a mutation in the LMNA gene, which is important for protecting DNA.
Down Syndrome
Down syndrome (also known as "Down's syndrome" or trisomy 21) is a condition that is caused when children are born with an extra copy of the 21st chromosome. Most people have two copies of all chromosomes, but people with Down syndrome have three copies of chromosome 21. Down syndrome affects between 1 in 800 and 1 in 1,000 people, according to the U.S. National Institutes of Health. The symptoms of Down syndrome range in severity from person to person, but almost all people afflicted with this genetic disorder have some form of mental impairment and slowed physical development.
Triple X Syndrome
Triple X syndrome is similar to Down syndrome in that it is the result of an extra chromosome (in this case, the X chromosome). As such, it only affects women. According to the Mayo Clinic, triple X syndrome does not always cause any identifiable symptoms. It can cause affected women to have an abnormally tall stature and an unusually small head (microcephaly). It can also cause skin folds to cover the corners of the eyes as well as some problems with physical and mental development.
Polycystic Kidney Disease
Polycystic kidney disease is caused by mutations in the PKD genes. This disease can be either autosomal dominant (meaning the person has the disease if only one copy of the gene is mutated) or autosomal recessive (both genes need to be mutated for the disease to occur), according to the National Institute of Diabetes and Digestive and Kidney Disorders. People with polycystic kidney disease develop numerous cysts on their kidneys that ultimately lead to kidney failure. Sufferers may also develop cysts in their livers or have abnormalities in other tissues throughout their bodies.
Tay-Sachs
Tay-Sachs disease is a disease caused by a defect in an enzyme called beta-hexosaminidase A, according to the Mount Sinai Medical Center. The enzyme is responsible for breaking down a chemical called GM2-ganglioside. If there is a problem with the enzyme, the GM2-ganglioside builds up in the nervous system, where it can rapidly reach toxic levels. Children with this disease have severe mental and physical impairments and may also develop characteristic red spots in their retinas. Most children with this disease die between the ages of 3 and 5 from pneumonia or other causes.
