Study of Chromosome Abnormalities in Pupils attending Special Schools in Tumakuru District and to correlate with Mental Retardation

Background: Mental Retardation is defined as a condition of incomplete development of the mind, characterized by impaired developmental skills. Chromosomal abnormalities are known to be an important cause of severe mental retardation. Aim: This study is done to identify the chromosomal abnormalities in pupils of special schools in Tumakuru District & to correlate it with mental retardation. Materials and methods: With the detailed history & written consent from the parents, a total number of 25 pupils from special schools in Tumakuru District were subjected to through clinical examination, following which blood samples were obtained and karyotyping was done at cytogenetic laboratory at Department of Anatomy, Sri Siddhartha Medical College, Tumakuru. Results are tabulated following which Genetic counseling was offered to the families of these children. Results: A review was carried out to establish the value of chromosome testing in children with significant developmental delay, where the aetiology was not evident clinically. Of the 25 pupils studied, 7 were girls and 18 were boys. A total of 4 i.e. 16% of the cases revealed an abnormal karyotype (2 boys & 2 girls). The advantages of chromosome testing in children with developmental delay in whom the etiology is not evident clinically are discussed. Conclusion: The control of genetic diseases should be based on integrated and comprehensive strategy combining best possible treatment and prevention through community education, population screening, genetic counselling & availability of early diagnosis. Recognition of parents with chromosomal abnormalities which can be inherited, is important, as the risk of recurrence is high in some cases.