What is Rothmund-Thomson syndrome?
Rothmund-Thomson is a rare genetic syndrome that affects multiple parts of the body. Many of the main symptoms affect the skin especially. The syndrome also presents with many unique physical features. Affected individuals are also at higher risk of cancer. There are around 300 reported cases of the syndrome worldwide currently.
This syndrome is also known as:
Poikiloderma Atrophicans and Cataract; Poikiloderma congenita; RTS
What gene changes cause Rothmund-Thomson syndrome?
Changes to the RECQL4, ANAPC1, DNA2 and CRIPT genes are responsible for causing the four types of the syndrome.
It is inherited in an autosomal recessive pattern.
Autosomal recessive inheritance means an affected individual receives one copy of a mutated gene from each of their parents, giving them two copies of a mutated gene. Parents, who carry only one copy of the gene mutation will not generally show any symptoms, but have a 25% chance of passing the copies of the gene mutations onto each of their children.
What are the main symptoms of Rothmund-Thomson syndrome?
- The main symptoms of the syndrome affect the skin of an affected individual. A common sign is a red rash on the cheeks that develops in infants between the ages of 3 and 6 months. This rash spreads to the arms and legs, over time. Other skin issues include changes in the coloring of the skin, skin thinning and clusters of blood vessels under the skin. These skin issues are known as poikiloderma.
- Unique facial features of the syndrome include sparse hair, sparse eyebrows and eyelashes. A clouding of the lens (cataracts) and consequent vision problems present in some affected individuals. Other characteristic physical features include growth delay and small stature, as well as teeth and nail abnormalities.
- Gastrointestinal issues are also common with the syndrome. These can include chronic diarrhea and vomiting.
The syndrome has also been associated with skeletal abnormalities- usually absent or malformed bones, fused bones a low bone mineral density. - Affected individuals have a higher risk of developing cancer. They are most at risk of developing a type of bone cancer known as osteosarcoma as well as more at risk of developing different types of skin cancer such as basal cell carcinoma and squamous cell carcinoma.
Possible clinical traits/features:
Decreased corneal thickness, Microcornea, Arthrogryposis multiplex congenita, Cryptorchidism, Craniosynostosis, Cutis marmorata, Epicanthus, Deeply set eye, Dermal atrophy, Delayed eruption of teeth, Limitation of joint mobility, Anemia, Dry skin, External ear malformation, Congenital hip dislocation, Juvenile zonular cataracts, Joint dislocation, Joint hypermobility, Irregular hyperpigmentation, Kyphoscoliosis, Abnormal immunoglobulin level, Increased number of teeth, Myelodysplasia, Intellectual disability, Short nose, Nausea and vomiting, Nephropathy, Neoplasm of the skin, Neoplasm of the stomach, Microphthalmia, Micrognathia, Mandibular prognathia, Microdontia, Cataract, Carious teeth, Aplasia/Hypoplasia of the thumb, Aplasia/Hypoplasia of the skin, Aplasia/Hypoplasia of the radius, Aplasia/Hypoplasia of the eyebrow, Abnormal sacrum morphology, Abnormality of the nail, Abnormality of the ulna, Abnormal blistering of the skin, Basal cell carcinoma, Abnormality of the genital system, Abnormal fingernails.
How is it diagnosed?
To find out if someone has a diagnosis of Rothmund-Thomson, it is important to have a consultation and evaluation with a clinical genetic specialist. Specialists may also suggest specific genetic testing or other types of tests to help reach a diagnosis. FDNA’s AI technology can help speed up the diagnostic process by analyzing facial features and other health information.
