Alkaptonuria News and Articles
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What is alkaptonuria?
Alkaptonuria is an inherited condition that causes urine to turn black when exposed to air. Ochronosis, a buildup of dark pigment in connective tissues such as cartilage and skin, is also characteristic of the disorder. People with alkaptonuria typically develop arthritis in adulthood, particularly in the spine and large joints.
How common is alkaptonuria?
The condition is rare, affecting 1 in 250,000 to 1 million people worldwide. Alkaptonuria is more common in certain areas of Slovakia (where it has an incidence of about 1 in 19,000 people) and in the Dominican Republic.
What genes are related to alkaptonuria?
Mutations in the HGD gene cause alkaptonuria.
The HGD gene makes an enzyme called homogentisate oxidase, which helps break down the amino acids phenylalanine and tyrosine (important building blocks of proteins) into smaller molecules. Mutations in the HGD gene prevent the enzyme from playing its role in this process. As a result, a substance called homogentisic acid builds up in the body. Excess homogentisic acid is deposited in connective tissues, which causes cartilage and skin to darken and leads to arthritis. Homogentisic acid is also in present in urine, which makes the urine turn dark when exposed to air.
How do people inherit alkaptonuria?
This condition is inherited in an autosomal recessive pattern, which means two copies of the gene in each cell are altered. Most often, the parents of an individual with an autosomal recessive disorder each carry one copy of the altered gene but do not show signs and symptoms of the disorder.
Source: National Institutes of Health
Recent Alkaptonuria News and Articles
Study Findings on Spinal Research Are Outlined in Reports from William Beaumont Hospital
2012 NOV 19 (NewsRx) -- By a News Reporter-Staff News Editor at Pain & Central Nervous System Week -- Research findings on Spinal Research are discussed in a new report. According to news originating from Royal Oak, Michigan, by NewsRx correspondents, research stated, "Case report. To report a rare case of alkaptonuria
presenting as a T1-hyperintense disc herniation."
Our news journalists obtained a quote from the research from William Beaumont Hospital, "Summary of Background Data. A 46-year-old man without previous diagnosis of alkaptonuria underwent evaluation for progressive back pain revealing a T1-hyperintense disc herniation at the L3-L4 level. Discectomy recovered a blackened disc that was pathologically confirmed to be nucleus pulposus with alkaptonuric involvement. The differential diagnosis of a T1-hyperintense, T2-hypointense disc on magnetic resonance imaging is discussed, with emphasis on the pathophysiology of alkaptonuria. A single patient is reported. Pathologically proven patient presentation with radiological and pathological images."
According to the news editors, the research concluded: "We report a rare case of alkaptonuria presenting as a T1-hyperintense disc herniation."
For more information on this research see: T1 Hyperintense Disc in Alkaptonuria. SPINE, 2012;37(21):E1361-E1363. SPINE can be contacted at: Lippincott Williams & Wilkins, 530 Walnut St, Philadelphia, PA 19106-3621, USA. (Lippincott Williams and Wilkins - www.lww.com; SPINE - journals.lww.com/spinejournal/pages/default.aspx)
The news correspondents report that additional information may be obtained from A.A. Sag, William Beaumont Hospital, Dept. of Pathol, Royal Oak, MI 48073, United States.
Keywords for this news article include: Michigan, Royal Oak, United States, Spinal Research, North and Central America
Our reports deliver fact-based news of research and discoveries from around the world. Copyright 2012, NewsRx LLC