Dyskeratosis congenita

Dyskeratosis congenita (DC) is an inherited disorder that affects the skin, mouth, and nails, among other parts of the body. These symptoms can appear at different ages and in different combinations. Typically individuals with DC will develop a lacy-looking discoloration on the face, neck and chest, white patches in the mouth and will have fingernails and toenails that are shaped abnormally. They may have eye or dental abnormalities, hair loss, short stature and a small head. Some may have a variable amount of delay of developmental skills. Individuals affected with DC are at an increased risk of developing certain life-threatening conditions, which include bone marrow failure, some forms of blood cancer and other cancers, and pulmonary fibrosis, a condition where scar tissue builds up in the lungs and reduces the amount of oxygen transported into the bloodstream. Intellect is usually normal in affected individuals. Life expectancy is not significantly shortened by DC. There is no cure for DC, but medical care and surveillance may help to improve some symptoms and overall condition of life. One of the causes of DC is pathogenic variants in the RTEL1 gene.

DC is inherited in different ways. DC associated with pathogenic variants in the RTEL1 gene is inherited in an autosomal recessive manner. This type of inheritance requires the presence of two copies of a pathogenic variant for a person to have the genetic disease. Both parents must be carriers of a pathogenic variant in the gene in order to be at risk to have an affected child. The child must inherit a pathogenic variant from each carrier parent in order to be affected. There is a 1 in 4 chance that a baby will inherit two mutated copies of the gene and be affected when both parents are carriers.

There are generally no signs or symptoms associated with being a carrier for DC. However, the risk to have a child affected with DC is increased. Testing of reproductive partners is recommended for carriers of DC.

It is unknown how often DC occurs in the general population.

The following websites may be informative: Genetic Home Reference: Dyskeratosis congenita (http://ghr.nlm.nih.gov/)

Gene Reviews: Dyskeratosis congenital (http://www.ncbi.nlm.nih.gov/books/NBK1116/) OMIM: [615190: DYSKERATOSIS CONGENITA, AUTOSOMAL RECESSIVE, 5] (http://www.ncbi.nlm.nih.gov/omim)

• Full gene sequencing