1. One of the Rare Diseases
Rothmund-Thomson Syndrome (RTS) is a very rare disease that currently affects a small number of people (approximately 300) around the world. The disease is also known by other names, including congenital poikiloderma, poikiloderma atrophicans and cataract, poikiloderma congenitale or poikiloderma congenitale of RTS. In at least 90% of cases, the disease manifests in the first year of life.
2. Patterns of Inheritance
Most people with RTS have a mutation on the gene known as RECQL4, located on chromosome 8. RTS follows an autosomal recessive inheritance pattern, meaning that each parent must carry the recessive gene in order to pass on the disease to a child. If each parent is a non-affected carrier of RTS, then each child has a 50% chance of also being an unaffected carrier. The child has a 25% of being neither symptomatic or a carrier. Unfortunately, the child has a 25% chance of having the disease.
3. Red Alert
The clinical manifestation of RTS varies greatly from one individual to another. While RTS affects many parts of the body, the skin is highly susceptible. Early in the first year of life, babies with RTS show redness on their cheeks, which eventually spreads to other parts of the body, such as the arms, legs and buttocks. Soon after the development of the redness, the skin shows signs of poikiloderma, evidenced by wide blood vessels under the skin, atrophy of the skin and reduced or enhanced pigmentation. Other symptoms include short stature, abnormal patterns of hair growth or baldness, cataracts, a saddle nose, a protruding jaw, poorly developed teeth, skeletal abnormalities affecting the hands and feet, atypical sexual development, bone cancer, and anemia.
4. Managing Symptoms
A dermatologist can treat skin symptoms as they arise. Typically, it's advised that people with RTS apply sunscreen to their skin prior to exposure to the sun and avoid exposure to sun whenever possible. Laser therapy may treat enlarged blood vessels, also known as telangiectases. Regular checks with an ophthalmologist permit early diagnosis of emerging cataracts. The use of surgical procedures treats skeletal malformations.
5. Looking Down the Road
While the disease becomes progressively worse during the first year of life, it appears to plateau soon after. A shorter life span mainly results from an increased risk of developing bone cancer. Therefore, most treating doctors take any sign of bone cancer seriously. Given the genetic component of RTS, siblings of an affected individual should seek genetic counseling prior to getting pregnant. Affected individuals do pass on the gene to all offspring. However, offspring won't be symptomatic unless the affected individual has a child with another affected individual or carrier.
