Navigation Links
Newly discovered gene variants lead to autism and mental retardation
Date:5/25/2010

Researchers working with Professor Gudrun Rappold, Director of the Department of Molecular Human Genetics at Heidelberg University Hospital, have discovered previously unknown mutations in autistic and mentally impaired patients in what is known as the SHANK2 gene, a gene that is partially responsible for linking nerve cells. However, a single gene mutation is not always enough to trigger the illness. In some cases, a certain threshold of mutation must be exceeded. The researchers conclude from their results that a correct inner structure of the nerve cell synapses is necessary to enable the normal development of language, social competence, and cognitive capacity. Essential for the success of the project were the studies by the Heidelberg research team with the doctoral student Simone Berkel and collaboration with a Canadian research team headed by Steve Scherer. The study has already been published online in the leading scientific journal Nature Genetics.

Autism is a congenital perception and information-processing disorder of the brain that is often associated with low intelligence, but also with above-average intelligence. The disease is characterized by limited social communication and stereotypical or ritualized behavior. Men are affected much more frequently than women. Autism and mental retardation can occur together but also independently of one another and are determined to a great extent by hereditary factors. Some of the responsible genes have already been identified but the precise genetic mechanisms have not yet been explained.

Genetic makeup of hundreds of patients analyzed

Professor Rappold and her team focused their studies on the SHANK2 gene, which encodes a structural protein at the nerve cell synapses. It is responsible for the mesh structure of the basic substance in the postsynapse. Only when the postsynapse is properly structured can nerve impulses be correctly transmitted. The researchers analyzed the genetic material of a total of 396 patients with autism and 184 patients with mental retardation. They found different mutations in their SHANK2 genes in the area of individual base pairs, but also variants in the number of gene copies. The mutations led to varying degrees of symptoms. None of the observed gene variants occurred in healthy control persons. "Apparently an intact postsynaptic structure is especially important for the development of cognitive functions, language, and social competence," explained Professor Rappold.

Identical mutations as the cause of different diseases

Some of the genetic mutations identified were new occurrences of mutations that were not inherited from the parents, but some of the mutations were also found in one parent. Since there are also healthy carriers of gene variants, we must assume that a certain threshold of gene mutations must be exceeded for the disease to appear. "Moreover, the same mutation can be present in an autistic patient with normal intelligence and in a mentally impaired patient," said Professor Rappold. There is some overlap in the clinical symptoms of mental retardation and autism, which can now be explained by a common genetic cause.


'/>"/>

Contact: Dr. Gudrun A. Rappold
gudrun_rappold@med.uni-heidelberg.de
49-62-215-65059
University Hospital Heidelberg
Source:Eurekalert

Related biology news :

1. Newly created cancer stem cells could aid breast cancer research
2. Newly-identified exercise gene could help with depression
3. Newly defined signaling pathway could mean better biofuel sources
4. Newly identified role for power plants in human cells could lead to targeted therapies
5. Death, division or cancer? Newly discovered checkpoint process holds the line in cell division
6. Newly described dragon protein could be key to bird flu cure
7. Leatherback turtles newly discovered migration route may be roadmap to salvation
8. Newly discovered monkey is threatened with extinction
9. Newly discovered molecular switch helps decide cell type in early embryo development
10. Genes newly explained effect on height may change tumor disorder treatment
11. Newly-discovered mechanism can explain the Beckwith-Wiedemann syndrome
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:5/9/2016)... , UAE, May 9, 2016 ... it comes to expanding freedom for high net worth ... Even in today,s globally connected world, there is still ... system could ever duplicate sealing your deal with a ... second passports by taking advantage of citizenship via investment ...
(Date:4/26/2016)... , April 27, 2016 ... the  "Global Multi-modal Biometrics Market 2016-2020"  report to ... ) , The analysts forecast the ... CAGR of 15.49% during the period 2016-2020.  ... number of sectors such as the healthcare, BFSI, ...
(Date:4/13/2016)... April 13, 2016  IMPOWER physicians supporting Medicaid patients ... a new clinical standard in telehealth thanks to a ... the higi platform, IMPOWER patients can routinely track key ... body mass index, and, when they opt in, share ... visit to a local retail location at no cost. ...
Breaking Biology News(10 mins):
(Date:6/23/2016)... ... June 23, 2016 , ... Supplyframe, the ... the Supplyframe Design Lab . Located in Pasadena, Calif., the Design Lab’s ... how hardware projects are designed, built and brought to market. , The Design ...
(Date:6/23/2016)... , June 23, 2016 Apellis Pharmaceuticals, ... 1 clinical trials of its complement C3 inhibitor, ... and multiple ascending dose studies designed to assess ... of subcutaneous injection in healthy adult volunteers. ... either as a single dose (ranging from 45 ...
(Date:6/23/2016)... , June 23, 2016 On Wednesday, ... at 4,833.32, down 0.22%; the Dow Jones Industrial Average edged ... closed at 2,085.45, down 0.17%. Stock-Callers.com has initiated coverage on ... ), Nektar Therapeutics (NASDAQ: NKTR ), Aralez Pharmaceuticals ... (NASDAQ: BIND ). Learn more about these stocks ...
(Date:6/23/2016)... ... June 23, 2016 , ... Velocity Products, ... tools designed, tuned and optimized exclusively for Okuma CNC machining centers at The ... of a collaboration among several companies with expertise in toolholding, cutting tools, machining ...
Breaking Biology Technology: