Dyskeratosis congenita (DC) is a very rare genetic disorder that affects approximately 1 in 1,000,000 people. A number of different gene mutations have been discovered that are linked to DC, all of which play some role in the biology of telomeres. Our genes are located on twisted, doubled-stranded molecules of DNA called chromosomes. At the ends of the chromosomes are stretches of DNA called telomeres, which protect our genetic data and make it possible for cells to divide. Telomeres have been compared with the plastic tips on shoelaces because they prevent chromosome ends from fraying and sticking to each other, which would scramble an organism’s genetic information to cause cancer, other diseases, or death.
Each time a cell divides, the telomeres get shorter. When they get too short, the cell no longer can divide and becomes inactive or “senescent” or dies. This process is associated with aging and cancer. The telomeres in people with DC are much shorter than normal and this leads to some cells not being able to regenerate normally.
DC is linked to a number of health conditions, including problems with skin, nails and hair, lungs, bones, blood, digestive system and the immune system. It can also cause learning difficulties, delays in reaching developmental milestones and make people prone to cancer and leukemia. The severity of symptoms range from mild to extreme. Over time, many people with DC develop bone marrow failure. Bone marrow failure means the marrow inside the bones doesn’t make enough of one or more kinds of blood cells the body needs.
Please visit Dyskeratosis Congenita Outreach for more information.