Bloom Syndrome - Causes and Care of a Rare Genetic Disorder

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What is Bloom Syndrome?

Bloom syndrome is a rare disorder where a person has a high frequency of breaks and rearrangements of their chromosomes. A person with Bloom syndrome is unusually small at birth and is of short stature throughout life. Although their bodies are very small, they are proportioned. A grown man with Bloom syndrome grows slightly taller than women with the condition, occasionally reaching just over 5 feet. Pigmentation changes occur causing sun-sensitivity, and red skin lesions that appear on the face can develop to affect the arms and the hands.

Although a person with Bloom’s syndrome is healthy overall, they are more likely to develop certain health problems. Lung problems such as pneumonia, bronchiectasis, and chronic lung diseases for example. Also, diabetes, benign and malignant tumors, develop at early age, earlier than in the general population.

An affected person’s reproductive ability is normal. Puberty is reached at a normal age and sexual interest and activity is the same as a non-affected person. Several woman have had normal children but menopause does occur at an early age. In some cases, men with BS have been tested to be infertile.

How is Bloom Syndrome Inherited?

Bloom syndrome is inherited in an autosomal recessive pattern meaning that an affected person receives two mutant BS genes, one from the father and one from the mother. This BS gene is named BLM. Although a person may carry the mutated BLM gene, they are healthy and of normal size. The risk of two carrier parents conceiving a child with BS is 25 percent with each pregnancy.

Bloom syndrome is a rare disease and its overall frequency is unknown. Bloom syndrome is more common in people of Central and Eastern European Jewish backgrounds. The chances of an Eastern European person inheriting this syndrome is 1 in 48,000. Approximately, one-third of people with Bloom syndrome are Ashkenazi Jewish decent.

Management of Bloom Disease

Since the growth hormone in a person affected with BS is normal, growth hormone therapy has not been able to improve their size.

A condition called gastro-esophageal reflux has been shown to be responsible for poor eating habits in BS infants can be treated with medications from their pediatricians. Also, the surgical placement of a tube in their upper intestinal tract can increase their fat deposits. Although these fat deposits are increased, linear growth is minimal.

The treatment for the red, sun-sensitive lesions requires proper protection. The avoidance of sunlight whenever possible is suggested. And when then the sun is not avoidable, sunscreen and suitable head covering is needed.

The development of all other conditions, diseases, and illnesses (cancer, lung disease) are treated normally. But the monitoring of a person’s health with BS is very important. Especially since the occurrence of these diseases can happen at an early age.


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