Bloom Syndrome

What is Bloom Syndrome?
Bloom syndrome is a rare genetic disorder that is characterised by short stature, sun-sensitive skin rash, and an increased risk of cancer.

What causes Bloom syndrome?
Bloom syndrome is caused by mutations (changes) in a gene called Bloom-Torre-Machacek (BLM), located at 15q26.1. The BLM gene codes a protein called BLM helicase, essential for DNA stability. Variants (genetic changes) within the BLM gene impair BLM helicase, thereby causing DNA instability and impacting how DNA stays intact.

How is Bloom syndrome passed on?
Bloom syndrome is an autosomal recessive condition, which means that both parents need to pass a changed version of the BLM gene for their child to develop the condition.

What are the symptoms of Bloom syndrome?
• Short and underweight
• Sun-sensitive rash such as a butterfly shaped red rash across the face, back of the hands and forearms
• Café-au-lait spots (light to dark pigmented spots)
• Telangiectasia: Small, red, “spider” veins commonly seen in the eyes
• Increased risk of certain cancers like leukaemia
• Diabetes
• Patchy loss of skin colour
• Dental abnormalities such as reduced number of teeth
• Infertility
• Polydactyly (increased number of fingers)
It is essential to recognise that the severity of these symptoms can vary among individuals

How do we diagnose Bloom syndrome?
Individuals suspected of having Bloom syndrome undergo a comprehensive diagnostic process, involving clinical assessments, genetic testing and laboratory tests. Radiological imaging and molecular genetic analysis will also be performed.

How do we manage Bloom syndrome?
Unfortunately, there is no cure for Bloom syndrome at present. A multi-disciplinary team, comprised of various healthcare individuals such as dermatologists, immunologists, geneticists and social workers, work on providing holistic care for individuals with Bloom syndrome. This includes monitoring for cancer with regular check-ups, treating skin conditions and managing the individual’s unique needs. The service in Manchester is headed by St Mary’s Hospital and is led by Dr Stefan Myer, a honorary consultant paediatric oncologist.

Credits:

Sharan Reghunathan – University of Mancheser 5th year medical student

 

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