Cytogenetics study in severely mentally retarded patients

Objectives: To study the frequency of chromosomal abnormalities in severely mentally retarded Iraqi patients. Secondly, to determine the types of chro mosomal abnormalities that play a major role in the causation of mental ret ardation and to compare our results with those reported elsewhere. Methods: Twenty one patients with severe mental retardation were subject to chromosomal analysis. The lymphocyte culture was carried out according to standard methods. Results: Fourteen of the subjected mentally retarded patients had chromosom al abnormalities, 13 autosomal abnormalities, and only one had sex chromoso mal abnormalities. However, structural autosomes were found to be the most prominent abnormalities and only 2 patients were demonstrated to have diagn osable syndrome. Conclusion: Chromosal abnormalities are an important cause of mental retard ation and its frequency increased with the severity of mental retardation. We concluded that chromosomal studies in mentally retarded patients help in accurate diagnosis and proper prognosis followed by genetic counseling and management rehabilitation.