Dyskeratosis congenita What is dyskeratosis congenita (DC)? Dyskeratosis congenita is an inherited condition causing premature ageing due to telomere repair abnormalities. Telomeres are sections of DNA found at the end of each chromosome which protect the chromosomes from deterioration and from merging with neighbouring chromosomes. Symptoms can include abnormalities of skin and nails, and in some cases, bone marrow failure (aplastic anaemia), or fibrosis (scarring) of lungs and liver cirrhosis. DC is associated with short telomere length. What causes dyskeratosis congenita? Dyskeratosis congenita is an inherited bone marrow failure, caused by a genetic defect leading to defective maintenance of telomeres, the genetic material at the end of our chromosomes. Each time a cell divides, its telomeres get a little shorter. With ageing, cells divide many times. After many cell divisions, the telomeres become too short and the cell dies. Depending on the type of cell, this may lead to medical problems, such as anaemia (when too many red blood cell producing cells have died) or lung fibrosis (when too many lung cells have died). Being born with a mutation in one of these genes doesn’t necessarily mean that you will get dyskeratosis congenita, but you may be at increased risk. You may be able to minimise this risk by lifestyle changes. Similarly, in some people with DC, no genetic abnormalities can be found. Two gene mutations (one from each parent) are generally required for dyskeratosis congenita. Parents who carry 1 gene mutation each have a 25% chance that each child will be affected. Links to aplastic anaemia Patients with dyskeratosis congenita run a high risk of developing aplastic anaemia. Bone marrow failure is the main cause of mortality in patients with DC. Who is affected? Dyskeratosis congenita usually affects children and young people, but can occasionally affect older people. Dyskeratosis Congenita is diagnosed in 1 in a million of general population. How can you get help? Patient support and information can be obtained by visiting the DC action website. The Gary Woodward Dyskeratosis Congenita Trust is a family run group that operates in England.