RÉSUMÉ
BACKGROUND : Mental health is an essential ingredient in the quality of life. Recent studies carried out in countries like Germany, USA, France, England and Belgium have provided evidence for the involvement of L1 (CAM) mutations in various X-linked mental retardation syndromes. L1 CAM is a neural cell adhesion molecule belonging to the superfamily of the immunoglobulins and is critical for proper CNS development in humans. AIM: This study was aimed to screen idiopathic mental retardation cases for L1 CAM mutations. MATERIALS AND METHODS : In this study, we screened 15 cases with mental retardation. Genomic DNA from the patients and control subjects was analyzed by polymerase chain reaction using specific primers. RESULTS : In 2 out of 15 patients, mutation was detected between exon 26 and 27. CONCLUSION : It is worthwhile to screen idiopathic mental retardation cases for L1 CAM mutations to reduce genetic morbidity in the population by offering genetic counseling and prenatal diagnosis.
RÉSUMÉ
Cytogenetic data obtained from investigating 1001 patients of Down syndrome (DS) and their parents over a period of 20 years (January 1979-January 1999) are presented. The frequency of pure trisomy, mosaicism and translocation was 87.92, 7.69 and 4.39 per cent respectively. The origin of the extra chromosome 21 due to meiotic non-disjunction was 79.24 per cent maternal and 20.76 per cent paternal. A high frequency of acrocentric chromosome associations was also observed in mothers of children of Down syndrome, this might have predisposed to an enhanced risk for non-disjunction. Birth order of DS showed a higher number of first and second borns. Reproductive performances of the parents indicated a high rate of abortions, compared to controls. Cytogenetic investigations carried out over these years greatly helped in the management of these children and for counseling the affected families.