A genetic disease is a terrible thing – an illness that is written into your very biological code that it can be very difficult to avoid or sometimes even impossible. For parents this can mean giving birth to someone who will never be ‘well’ in the traditional sense, and no amount of exercise or healthy living can help that.
The fortunate news is that genetic disorders are relatively uncommon, but that said they are still a real danger and some are certainly more common than others. Here we will look at some of the most common genetic diseases, in no particular order.
Cystic Fibrosis: The most common genetic disease is cystic fibrosis, which is a condition affecting around 30,000 Americans. This condition causes an abnormality in the fluids of the lungs which causes a chronic infection and also affects the pancreas, liver and intestine. Other symptoms caused by this include poor growth and weight gain, infertility in males and a salty tasting skin.
Haemophilia: In haemophilia the blood doesn’t clot properly when the patient is injured which leads to continual blood loss. Of course this can be highly dangerous and means that what would be a minor accident for anyone else can become a life threatening injury. It also causes complications during surgery and it’s important that those with haemophilia identify themselves as suffering with it.
Sickle Cell Anaemia: Sickle cell anaemia is genetic condition affecting many people in America and Africa in particular, where the red blood cell becomes ‘sticky’ and ‘C-shaped’ and loses oxygen. These cells then block the blood vessels causing pain, tiredness and damage to the organs.
Down Syndrome: Down syndrome or DS is a chromosomal syndrome which occurs as a result of an extra chromosome and is the most common disorder of that type. Symptoms include distinctive spacing of the facial features, impaired cognitive ability, stunted physical growth and an increased risk of congenital heart disease.
Huntington’s Disease: Huntington’s disease actually isn’t highly common, affecting around 5-10 individuals in every 100,000, but the severity of the symptoms and the relative prevalence in the West means it’s one of the better known conditions. This is an autosomal dominant mutation that can affect either of the two copies of any gene giving a child a 50% chance of inheriting the condition. Symptoms normally begin between the age of 35 and 40, and cause gradual cognitive decline (it is related to Alzheimer’s) followed by impairment in physical ability until the individual begins to find any kind of movement incredibly difficult.
Thalassemia: This is a condition affecting the blood in which the body doesn’t produce enough red blood cells or alternatively does not produce them efficiently enough resulting in a heightened chance of anaemia.
Tay-Sachs: Tay-Sachs is a serious and ultimately fatal condition in which an enzyme called ‘hexosaminidase’ is missing resulting in the progressive deterioration of both cognitive and physical function as a result of the degradation of the central nervous system.
Angelman Syndrome: Angelman syndrome is a neurogenetic disorder which causes intellectual disability as well as sleep disturbances, jerky movements, frequent laughter and smiling and an ‘unusually’ upbeat disposition. Sufferers may also have a more ‘youthful’ appearance (and a delayed growth in head circumference) and hypopigmentation. It is caused by the lack of the maternal element of chromosome 15.
Duchenne Muscular Dystrophy: DMD is a recessive X-linked condition causing muscular dystrophy and ultimately death and affects around 1 in 3,600 boys beginning before the age of five. As the condition progresses it can cause abnormal bone developments and usually the aid of a wheelchair will be necessary by the age of 12.
There are many other types of genetic disorders from fatal familial insomnia to colour blindness – though many of these are either very rare (the former) or not typically considered ‘diseases’ (the latter). Meanwhile many of the other conditions and illnesses that we experience have a genetic element, and it is possible to be genetically more ‘prone’ to conditions such as diabetes and even obesity.