Bloom syndrome is a rare inherited disorder characterized by a high frequency of breaks and rearrangements in an affected person's chromosomes, discovered and first described by dermatologist Dr. David Bloom in 1954.^[1] The International Statistical Classification of Diseases and Related Health Problems (most commonly known by the abbreviation ICD) provides codes to classify diseases and a wide variety of signs, symptoms, abnormal findings, complaints, social circumstances and external causes of injury or disease. ... The following is a list of codes for International Statistical Classification of Diseases and Related Health Problems. ... The Mendelian Inheritance in Man project is a database that catalogues all the known diseases with a genetic component, and - when possible - links them to the relevant genes in the human genome. ... The Disease Bold textDatabase is a free website that provides information about the relationships between medical conditions, symptoms, and medications. ... eMedicine is an online clinical medical knowledge base that was founded in 1996. ... Medical Subject Headings (MeSH) is a huge controlled vocabulary (or metadata system) for the purpose of indexing journal articles and books in the life sciences. ... A scheme of a condensed (metaphase) chromosome. ...

Presentation

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. f you all The blood vessels are part of the circulatory system and function to transport blood throughout the body. ...

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. Mental retardation is a term for a pattern of persistently slow learning of basic motor and language skills (milestones) during childhood, and a significantly below-normal global intellectual capacity as an adult. ... This article is about the disease that features high blood sugar. ... In medicine, immune deficiency (or immunodeficiency) is a state where the immune system is incapable of defending the organism from infectious disease. ... This article is about human pneumonia. ... A spermatozoon or spermatozoan ( spermatozoa), from the ancient Greek σπέρμα (seed) and (living being) and more commonly known as a sperm cell, is the haploid cell that is the male gamete. ... Menopause is the physiological cessation of menstrual cycles associated with advancing age in women. ...

Relationship to cancer

Chromosomal instability in Bloom syndrome results in a high risk of cancer in affected individuals. 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. Cancer is a class of diseases or disorders characterized by uncontrolled division of cells and the ability of these to spread, either by direct growth into adjacent tissue through invasion, or by implantation into distant sites by metastasis (where cancer cells are transported through the bloodstream or lymphatic system). ...

Genetics

Mutations in the BLM gene (locus 15q26.1) cause Bloom syndrome. The BLM gene provides instructions for producing a protein called the Bloom (BLM) syndrome protein, which is a member of the DNA helicase family. DNA helicases are enzymes that unwind the two spiral strands of a DNA molecule so that they can be copied. When a cell prepares to divide to form two cells, the chromosomes are duplicated so that each new cell will get a complete set of chromosomes; this replication process involves unwinding the DNA so that it can be copied. The BLM protein is important in maintaining the stability of the DNA during this process. Mutations in the BLM gene alter or reduce the BLM protein's DNA helicase activity, which causes errors in the copying process during replication. As a result, people with Bloom syndrome have a higher frequency of chromosome breakage and rearrangement than unaffected people. This increase in chromosome breakage and rearrangement leads to the signs and symptoms of Bloom syndrome. Another suggestion put forward is that people with Bloom syndrome overproduce the superoxide anion, whose volatility damages the affected person's chromosomes. Helicase is an enzyme vital to all living organisms. ... DNA replication. ... Lewis electron configuration of superoxide. ...

Bloom syndrome is inherited in an autosomal recessive fashion. Both parents must be carriers in order for a child to be affected. The carrier frequency in individuals of Eastern European ancestry is about 1/100. If both parents are carriers, there is a one in four, or 25%, chance with each pregnancy for an affected child. Genetic counseling and genetic testing is recommended for families who may be carriers of Bloom syndrome. This article or section does not adequately cite its references or sources. ... In genetics, the term recessive gene refers to an allele that causes a phenotype (visible or detectable characteristic) that is only seen in a homozygous genotype (an organism that has two copies of the same allele). ... Genetic counseling is the process by which patients or relatives, at risk of an inherited disorder, are advised of the consequences and nature of the disorder, the probability of developing or transmitting it, and the options open to them in management and family planning in order to prevent, avoid or... Genetic testing allows the genetic diagnosis of vulnerabilities to inherited diseases, and can also be used to determine a persons ancestry. ...

See also

• Accelerated aging disease
• Bloom syndrome (gene)
• DNA repair
• Progeria

An accelerated aging disease is a genetic disorder in which various tissues, organs or systems of the human body age prematurely. ... Orthologs Human Mouse Entrez Ensembl Uniprot Refseq Location Pubmed search Bloom syndrome, also known as BLM, is a human gene. ... DNA damage resulting in multiple broken chromosomes DNA repair refers to a collection of processes by which a cell identifies and corrects damage to the DNA molecules that encode its genome. ... The term Progeria narrowly refers to Hutchinson-Gilford Progeria syndrome, but the term is also used more generally to describe any of the so-called accelerated aging diseases. The word progeria is derived from the Greek for prematurely old. Because the accelerated aging diseases display different aspects of aging, but...

References

1. ^ Bloom D (1954). "Congenital telangiectatic erythema resembling lupus erythematosus in dwarfs; probably a syndrome entity". A.M.A. American journal of diseases of children 88 (6): 754-8. PMID 13206391. 

• Overview of condition at NLM Genetics Home Reference

The U.S. National Library of Medicine (NLM), operated by the U.S. federal government, is the worlds largest medical research library. ...

External links

• BLOOM'S SYNDROME FOUNDATION - devoted to medical & scientific research to discover a treatment or cure for Bloom's Syndrome
• DNA Repair
• Segmental Progeria
• Article on Bloom's Syndrome
• Blooms Connect - a forum for people with Bloom's Syndrome and their loved ones