Role oF Cyogenetic Analysis In Establishing A Syndromic Diagnosis In Kids With Abnormal Phenotype

Chromosomal abnormalities count for a large proportion of cases of congenital malformation and/or mental retardation and dysmorphic features. Specific chromosomal abnormalities are responsible for more than 70 identified syndromes. Chromosomal abnormalities may be either numerical or structural and may involve one or more autosomes,sex chromosomes or both.In this study cytogenetic analysis was carried out on 50 new- borns and children with dysimorphic features and/or multiple congential anomalies and unclassified mental retardation suggestive of underlying chromosomal aberrations, from Children Hospital of Zagazig university and some out patient clincs. Their ages ranged from few days to 9 years.All the patients were subjected to full history taking, complete clinical examination, radiological study and cytogenetic analysis using high resolution technique to identify any abnormality or micro deletion that can not be detected by routine Giemsa banding.For every case, at least 20 metaphases were counted, 5 metaphases were analyzed and tow or more cells were karyotyped, but if mosaicism is susbected 50 or more cells count were under taken. Of 50 patients on whom chromosomal analysis was done, chromosomal aberration were detected in 13 patients (26%).