Bloom syndrome is an inherited disorder characterized by a high
frequency of breaks and rearrangements in an affected person's chromosomes.
People with Bloom syndrome are much smaller than average, and often
have a high-pitched voice and characteristic facial features including
a long, narrow face; small lower jaw; and prominent nose and ears.
They tend to develop pigmentation changes and dilated blood vessels
in the skin, particularly in response to sun exposure. These changes
often appear as a butterfly-shaped patch of reddened skin on the
face. The skin changes may also affect the hands and arms.
Other features of the disorder may include learning disabilities,
mental retardation, chronic lung problems, diabetes, and immune
deficiency that leads to recurrent pneumonia and ear infections.
Men with Bloom syndrome usually do not produce sperm, and as a result
are unable to father children (infertile). Women with the disorder
generally experience menopause earlier than usual.
Bloom syndrome confers a 150-300 times increased risk of cancer
as compared to the general population, causing life expectancy to
be shortened. Affected individuals develop the full range of cancers
found in the general population, but the cancers arise unusually
early in life. People with Bloom syndrome may be first diagnosed
with cancer at about 25 years old.
Bloom syndrome is a very rare disorder in most populations but
is more common in people of Central and Eastern European (Ashkenazi)
Jewish background, among whom 1 in 48,000 are affected. Approximately
one third of people with Bloom syndrome are of Ashkenazi Jewish
descent, and approximately 1 in 104 people with Ashkenazi Jewish
ancestry is a carrier of Bloom syndrome.
offers Ashkenazi Jewish Carrier
Screening for $262 to $1219 depending on the tests ordered. Individuals
with Bloom syndrome have two copies of a gene mutation, one copy
inherited from each parent. Neither gene in the pair is working
correctly, which causes the symptoms of the disease. A carrier of
Bloom syndrome is a person who has a mutation in one gene of the
pair. Carriers are unaffected with the disease because the properly
working gene is able to compensate for the gene that contains the
mutation, but they are at risk of passing the gene mutation on to