Genetic Disorders Causing Mental Retardation

Scientists in the United States identified the genetic disorder that causes retardation or mental retardation and epilepsy. Disturbance of small segments of DNA code is missing, as revealed by the research team leader from the Faculty of Medicine, University of Washington Evan Eichler, also cause malformations, the abnormality of form or structure of organs.

Evan Eichler led the team consists of 33 researchers from the U.S., Italy and Britain to menscreening entire genomes of 757 individuals with mental retardation. Syndrome is still not known his name is associated with a small segment of DNA code found in one out of 330 cases of retardation with the causes that have not been clear. This syndrome is estimated to affect one out of 40,000 general population.


Two study participants who had no known family relationship nukleotid shortage of 1.5 million genetic code that is located on Chromosome 15 and runs on 6 different genes. Generally there are about 3 billion nukleotid on the human genome.

One of the genes known to CHRNA7 responsible for the important role of proteins that deliver messages to the brain cells. Disturbances in this gene are also associated with epilepsy and schizophrenia.

After knowing the genome being studied, Eichler then menscreening 1040 other individuals who have mental retardation using data from the Greenwood Genetic Center of the Greenwood Genetic Center in South Carolina. These individuals, half of them of European descent and the other half-African American descent.

Seven other study participants known to have similar genetic disorders and suffer the same symptoms. Of the nine cases found, all showed the medium to mild retardation. From inspection of electronic activity of the brain known seven study participants known to suffer epilepsy. The participants of this study also has certain abnormal facial characteristics.

The researchers predict another minority syndrome likely arise through a high-resolution scans for the elimination of "sub-microscopic" in the human genetic code.