ABSTRACT
Various chromosomal abnormalities have been found in patients with epilepsy and epileptic syndromes. Genetic linkage and karyotype analysis may provide cytogenetic clues leading to the identification of genes linked to specific types of epilepsy. This study is aimed to evaluate the chromosomal abnormalities and specific chromosomal regions in cases of childhood epilepsy with dysmorphism. The present study included 40 epileptic patients with dysmorphic features, 22 males and 18 females, their ages ranged between 27 months and 9.5 years with mean and standard deviation 4.32 +/- 2.89 years All patients had at least two attacks of unprovoked afebrile seizures greater than 24 hours apart. A thorough history taking about fits, general as well as neurological examination with special emphasis on any associated anomalies. EEG, IQ and CT were carried out in all patients, while MRI brain was done for some cases. Chromosomal study included karyotyping and fluorescence in situ hybridization [FISH] were done for all cases. Our results showed: 22 [55%] patients had normal karyotype [first group] while 18 patients [45%] had chromosomal aberrations [second group]. The frequency of various types of chromosomal aberrations among the studied patients was: Eight patients [44%] had trisomy 21 [Down syndrome], three patients [16.5%] had Turner [45x] syndrome, one patient [5.5%] had trisomy 18 [Edwards syndrome], one patient [5.5%] had deletion of short arm of chromosome 18 one patient [5.5%] had deletion of long arm of chromosome 15 [Angelman syndrome], one patient [5.5%] had deletion of long arm of chromosome 13, one patient [5.5%] had deletion of long arm of chromosome 7 [Williams syndrome], one patient [5.5%] has deletion of long arm of chromosome 4 and one patient [5.5%] had duplication of long arm of chromosome 20. There was significant difference between the two groups in developmental milestones. Consanguineous marriage was found in 22.7% of the first group versus 33% of second group. Cerebral atrophy was found in three patients [13.5%] of the first group and in five patients [27.5%] of the second group. Cerebellar atrophy was found in one patient [5.5%] of the second group. A genesis of corpus callosum was found in one patient [5.5%] of the second group. The present study reinforces the findings of the significant association between some chromosomal aberrations and epilepsy. These include: Trisomy 21, trisomy 18, Turner syndrome and abnormallties of regions 4q, 7q and 15q. Other regions associated with epilepsy were decteded: 13q, 18p and 20q. Further investigation into these regions may lead to discovery of new genes involved in epileptogenesis. The present study directs the attention of the clinicians about the importance of dysmorphic features in the evaluation of epileptic patients. In recommendation, karyotype should be performed in a child with seizures and dysmorphic features. Further advanced molecular studies about genetic basis of epilepsy are recommended