Rothmund-Thomson syndrome

What it is, symptoms and effects

From: MedlinePlus Genetics, National Library of Medicine

Rothmund-Thomson syndrome is a rare condition that affects many parts of the body, especially the skin. People with this condition typically develop redness on the cheeks between ages 3 months and 6 months. Over time the rash spreads to the arms and legs, causing patchy changes in skin coloring, areas of thinning skin (atrophy), and small clusters of blood vessels just under the skin (telangiectases). These skin problems persist for life and are collectively known as poikiloderma.

Rothmund-Thomson syndrome is also characterized by sparse hair, eyebrows, and eyelashes; slow growth and small stature; abnormalities of the teeth and nails; and gastrointestinal problems in infancy, such as chronic diarrhea and vomiting. Some affected children develop a clouding of the lens of the eye (cataract), which affects vision. Many people with this disorder have skeletal abnormalities including absent or malformed bones, fused bones, and low bone mineral density (osteopenia or osteoporosis). Some of these abnormalities affect the development of bones in the forearms and the thumbs, and are known as radial ray malformations.

People with Rothmund-Thomson syndrome have an increased risk of developing cancer, particularly a form of bone cancer called osteosarcoma. These bone tumors most often develop during childhood or adolescence. Several types of skin cancer, including basal cell carcinoma and squamous cell carcinoma, are also more common in people with this disorder.

The varied signs and symptoms of Rothmund-Thomson syndrome overlap with features of other disorders, namely Baller-Gerold syndrome and RAPADILINO syndrome. These syndromes are also characterized by radial ray defects, skeletal abnormalities, and slow growth. All of these conditions can be caused by mutations in the same gene. Based on these similarities, researchers are investigating whether Rothmund-Thomson syndrome, Baller-Gerold syndrome, and RAPADILINO syndrome are separate disorders or part of a single syndrome with overlapping signs and symptoms.

Causes and biological mechanisms

From: MedlinePlus Genetics, National Library of Medicine

Mutations in the RECQL4 gene cause about two-thirds of all cases of Rothmund-Thomson syndrome. This gene provides instructions for making one member of a protein family called RecQ helicases. Helicases are enzymes that bind to DNA and temporarily unwind the two spiral strands (double helix) of the DNA molecule. This unwinding is necessary for copying (replicating) DNA in preparation for cell division, and for repairing damaged DNA. The RECQL4 protein helps stabilize genetic information in the body's cells and plays a role in replicating and repairing DNA.

RECQL4 mutations lead to the production of an abnormally short, nonfunctional version of the RECQL4 protein or prevent cells from making any of this protein. A shortage of the RECQL4 protein may prevent normal DNA replication and repair, causing widespread damage to a person's genetic information over time. It is unclear how a loss of this protein's activity leads to the specific features of Rothmund-Thomson syndrome.

In about one-third of individuals with Rothmund-Thomson syndrome, no mutation in the RECQL4 gene has been found. The cause of the condition in these individuals is unknown; however, researchers suspect that these cases may result from mutations in a gene related to the RECQL4 gene.

In some cases, chromosomal abnormalities have been identified in people with Rothmund-Thomson syndrome. These abnormalities include extra or missing genetic material, usually from chromosome 7 or chromosome 8, in some of an affected person's cells. Researchers believe that these chromosomal changes arise because of the overall instability of an affected person's genetic information; they do not cause the disorder.

Inheritance and family implications

From: MedlinePlus Genetics, National Library of Medicine

This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition.

How common is it?

From: MedlinePlus Genetics, National Library of Medicine

Rothmund-Thomson syndrome is a rare disorder; its incidence is unknown. About 300 people with this condition have been reported worldwide in scientific studies.

Reported clinical features and what the terms mean

The following findings are associated with this condition in Orphanet. They are not a checklist for diagnosing yourself, and they do not all occur in every affected person. Some are examination, imaging or laboratory findings that cannot be recognised at home.

The frequency labels describe how often a finding was reported among people with the condition in the source. They do not give the chance that a person with that symptom has the condition. Definitions below reproduce HPO terminology; they explain the term, not the likely severity in an individual.

Malar rash · Very frequent (99-80%)

An erythematous (red), flat facial rash that affects the skin in the malar area (over the cheekbones) and extends over the bridge of the nose.

Poikiloderma · Very frequent (99-80%)

Poikiloderma refers to a patch of skin with (1) reticulated hypopigmentation and hyperpigmentation, (2) wrinkling secondary to epidermal atrophy, and (3) telangiectasias.

Skin rash · Very frequent (99-80%)

A red eruption of the skin.

Abnormal blistering of the skin · Frequent (79-30%)

The presence of one or more bullae on the skin, defined as fluid-filled blisters more than 5 mm in diameter with thin walls.

Abnormality of the dentition · Frequent (79-30%)

Any abnormality of the teeth.

Abnormality of the skeletal system · Frequent (79-30%)

An abnormality of the skeletal system.

Palmar hyperkeratosis · Frequent (79-30%)

Abnormal thickening of the skin localized to the palm of the hand.

Plantar hyperkeratosis · Frequent (79-30%)

Hyperkeratosis affecting the sole of the foot.

Other findings in the same source

From: Orphanet

Additional reported features include Reduced bone mineral density (Frequent (79-30%)); Reticular hyperpigmentation (Frequent (79-30%)); Short stature (Frequent (79-30%)); Small for gestational age (Frequent (79-30%)); Sparse eyebrow (Frequent (79-30%)); Sparse eyelashes (Frequent (79-30%)); Sparse hair (Frequent (79-30%)); Infertility (Frequent (79-30%)); Abnormal nail morphology (Occasional (29-5%)); Abnormal trabecular bone morphology (Occasional (29-5%)). This is a selected summary, not a complete description of the condition.

Which doctor should you see?

The suggested department for discussing Rothmund-Thomson syndrome is Clinical Genetics, with a clinical geneticist as the relevant type of clinician. Paediatrician (children) or physician (adults), with clinical geneticist referral.

This is an editorial referral starting point. The appropriate clinic depends on the person’s age, symptoms, previous diagnosis and local services. The first clinician can decide whether another specialty or a team is needed; a department label does not confirm the diagnosis.

How to prepare for an assessment

Bring a short timeline of the main symptoms: when they first appeared, whether they are constant or episodic, what seems to change them, and how they affect daily activities. Include previous reports, discharge summaries, current medicines and supplements, allergies, and any relevant family history. A dated record is more useful than trying to match every feature in an online article.

Ask the clinician what is already established and what remains uncertain. If a test is suggested, ask what question it answers, what its limitations are and how the result would change the next step. The information here is not an instruction to arrange every possible test. In children, bring growth, developmental and school information if it is relevant to the concern.

• Does the exact genetic or chromosome finding explain the observed features?
• Would a genetic counsellor help the family understand the result?
• Which organ-specific assessments are appropriate for this particular diagnosis?

Treatment discussions and follow-up

The material gathered for this draft does not provide a complete condition-specific treatment pathway for Rothmund-Thomson syndrome. That gap does not mean that treatment is unavailable. A clinician needs to establish the diagnosis and review current guidance before recommending medicines, procedures, rehabilitation or other support.

Before leaving the appointment, clarify the next review date, who will communicate results, and whom to contact if the situation changes. Discuss difficulties with sleep, work, school, mobility, eating or emotional wellbeing when these are relevant. Practical support may require coordination between the treating clinician and other services.

The collected references do not establish a complete prevention or long-term outlook section for this entry. Missing information should not be interpreted as proof that prevention is impossible or that a particular outcome is inevitable. Ask what is known for the exact subtype, stage and personal circumstances, and which uncertainties remain.

When to seek emergency help

Severe breathing difficulty, collapse, new stroke-like symptoms, a seizure that is prolonged or repeated without recovery, uncontrolled major bleeding, or an immediate risk of self-harm require emergency help. In India, call 112 or reach the nearest emergency department. This is a general, non-exhaustive warning list; it is not a condition-specific triage tool.