Bloom Syndrome

Why in News?

Recently, a 12-year-old girl with Bloom Syndrome underwent a bone marrow transplant (BMT) using stem cells from her younger brother at a private hospital in Chennai.

• It is a rare genetic disorder, characterised by short stature and blood-related complications, and carries a risk of blood cancers such as acute myeloid leukemia.
• People with Bloom syndrome are usually smaller than 97% of the population in both height and weight from birth, and they rarely exceed 5 feet tall in adulthood.
• Causes - Bloom Syndrome is an autosomal recessive genetic disorder, meaning a person must inherit 2 copies of the mutated BLM gene, one from each parent.
• The BLM gene provides instructions for making a protein called a RecQ helicase, which is crucial for DNA stability.
• Mutations in the BLM gene lead to a non-functional BLM protein, resulting in genomic instability and a high number of chromosomal breaks.
• Symptoms
  • Growth Deficiency - Individuals typically experience severe growth delays both before and after birth.
  • Photosensitive Skin - A characteristic butterfly-shaped rash develops on the face after sun exposure, along with telangiectases (small, enlarged blood vessels) and other skin changes.
  • Increased Cancer Risk - There is a greatly increased risk of developing many types of cancer, often at an early age.
  • Immune Deficiencies - People with Bloom Syndrome may have immune system issues, making them more vulnerable to infections.
  • Other Complications - These can include insulin resistance, an increased risk for diabetes, and chronic obstructive pulmonary disease.
• No Cure - There is currently no treatment that targets the underlying genetic cause of the disorder.
• Recent case - The girl had
  • Monosomy 7, a chromosomal abnormality involving the loss of one copy of chromosome 7, and
  • Myelodysplastic Syndrome (MDS), a disorder in which the bone marrow fails to produce healthy blood cells.
• There is a risk of MDS progressing to leukemia.
• She underwent bone marrow transplant (BMT) using stem cells from her younger brother.

Reference

The Hindu | Bloom Syndrome