Navigation Links
Aberrations in region of chromosome 1q21.1 associated with broad range of disorders in children
Date:9/10/2008

Researchers have discovered a submicroscopic aberration in a particular region of human chromosome 1q21.1 that appears to be associated with a variety of developmental disorders in children. The aberration can manifest itself as unexplained mild or moderate mental retardation, growth retardation, learning disabilities, seizures, autism, heart defects, other congenital abnormalities, cataracts, small head size, unusual facial features, hand deformities, or skeletal problems. Some people who have the aberration are only slightly affected or apparently unaffected, others are more seriously impaired.

The multinational research was led by Dr. Heather C. Mefford, acting assistant professor of pediatrics at the University of Washington, and Dr. Andrew J. Sharp of the University of Geneva Medical School in Switzerland. Mefford practices medical genetics at Children's Hospital and Regional Medical Center in Seattle and the UW Medical Center Medical Genetics Clinic.

The results will be published in the Sept. 11 New England Journal of Medicine in an article titled, "Recurrent Rearrangements of Chromosome 1q21.1 and Variable Pediatric Phenotypes." The results are discussed in an accompanying editorial by David H. Ledbetter of Emory University in Atlanta.

Deletions and duplications of major sections of the human genome have long been known to cause disease or make a person susceptible to disease. Recent technological advances, called cytogenetic arrays, are enabling scientists to test large numbers of people to determine the presence or absence of submicroscopic imbalances in small sections of their chromosomes.

Using these new advances, the researchers checked for the presence of microdeletions and microduplications in a specific region of chromosome 1q21.1 in groups of patients with unexplained mental retardation, autism, or congenital abnormalities, and compared their findings with similar testing of a group from the general population. In these 4,737 controls from the general population, no microdeletions were found. Two controls had one small duplication at the far end of the region under study, and only one had duplication of the entire region.

The authors explained that the genomic structure of 1q21.1 is extremely complex. There are still 15 assembly gaps, or 700 kb of missing sequence in 1q21.1, in the most recent map of the human genome.

These gaps, the researchers noted, might contain as yet unknown genes that contribute to the differences in the types of developmental abnormalities that occur in children with the deletion. Supposedly unaffected deletion carriers might in fact have more subtle disorders that could be found during further clinical evaluations. For example, an examination of one apparently unaffected carrier revealed mild cataracts and a heart defect that were previously undetected.

Studies by other groups of researchers have also found a connection between 1q21.1 deletions and schizophrenia in some people, and parts missing in the reproductive tract in other people. These results, the authors of the Sept. 11 New England Journal of Medicine article noted, confirm the association of 1q21.1 rearrangements with a broad spectrum of disorders, and also further dispel the notion that such rearrangements will necessarily follow the one-gene, one-disease model.

The authors recognize that the diversity of disorders and the lack of a distinct syndrome accompanying 1q21.1 rearrangements will complicate genetic diagnosing and counseling. They suggest that clinicians caring for patients who have unexplained developmental abnormalities consider the identification of a 1q21.1 rearrangement in a patient a significant clinical finding and probably an influential genetic factor contributing to the patient's disorder. Evaluating the patient's family members may reveal apparently unaffected or mildly affected relatives carrying the same rearrangement. Keeping in mind the many possible repercussions of having this rearrangement in the chromosome, the authors suggest that young carriers should be monitored over the long term for the emergence of learning disabilities, autism, schizophrenia, or other neuropsychiatric disorders.

This study, the authors said, adds 1q21.1 as a chromosomal locus to the growing list of structural variants that might eventually be included in genetic screening panels for people with developmental delays or neuropsychiatric diagnoses.

"Counseling in the prenatal setting," the researchers wrote, "will present the greatest challenge: although the likelihood of an abnormal outcome is high in a person with a 1q21.1 rearrangement, current knowledge does not allow us to predict which abnormality will occur in any given person."


'/>"/>

Contact: Leila Gray
206-685-0381
University of Washington
Source:Eurekalert

Related biology news :

1. Experts meet on need for new rules to govern worlds fragile polar regions
2. Unexplored Arctic region to be mapped
3. Regional Law Enforcement Data Exchange System Expands
4. Colorado Rocky Mountain Region: A Geological Cornucopia
5. Wisconsin Governor Jim Doyle to receive Regional Policy Award from ESA
6. NJIT architect professor advocates best-building practices for high wind regions
7. Titanium Group to Attend Regional ICT Meeting in Thailand
8. Regional nuclear conflict would create near-global ozone hole, says CU-Boulder study
9. Sudden ecosystem flips imperil worlds poorest regions, say water experts
10. Brown hosts regional bioengineering conference
11. Harlequin frog rediscovered in remote region of Colombia
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/14/2017)... , June 15, 2017  IBM (NYSE: IBM ) is ... tech event dedicated to developing collaboration between startups and global ... June 15-17. During the event, nine startups will showcase the ... in various industries. France ... international market, with a 30 percent increase in the number ...
(Date:4/24/2017)... WASHINGTON , April 24, 2017 ... counsel and partner with  Identity Strategy Partners, LLP ... "With or without President Trump,s March 6, ... Foreign Terrorist Entry , refugee vetting can be instilled ... refugee resettlement. (Right now, all refugee applications are ...
(Date:4/13/2017)... According to a new market research report "Consumer ... Administration, and Authorization), Service, Authentication Type, Deployment Mode, Vertical, and Region - ... to grow from USD 14.30 Billion in 2017 to USD 31.75 Billion ... ... MarketsandMarkets Logo ...
Breaking Biology News(10 mins):
(Date:10/10/2017)... ... 10, 2017 , ... The Pittcon Program Committee is pleased ... scientists who have made outstanding contributions to analytical chemistry and applied spectroscopy. Each ... leading conference and exposition for laboratory science, which will be held February 26-March ...
(Date:10/9/2017)... ... 09, 2017 , ... The award-winning American Farmer television series will feature 3 ... airs Tuesdays at 8:30aET on RFD-TV. , With global population estimates nearing ten ... to continue to feed a growing nation. At the same time, many of our ...
(Date:10/9/2017)... Phoenix, Arizona (PRWEB) , ... October 09, 2017 ... ... of Kindred, a four-tiered line of medical marijuana products targeting the needs of ... production and packaging of Kindred takes place in Phoenix, Arizona. , As operators ...
(Date:10/7/2017)... ... October 06, 2017 , ... ... consulting for microscopy and surface analysis, Nanoscience Instruments is now expanding into ... a broad range of contract analysis services for advanced applications. Services will ...
Breaking Biology Technology: