Duane's retraction syndrome and karyotypic abnormalities
• Aim: To evaluate chromosome 8 abnormalities in Duane's retraction syndrome (DRS) type I. • Methods: We evaluated chromosome 8 abnormalities in 29 consecutive cases of DRS type I. DNA was isolated from the peripheral leukocytes of patients using a genomic DNA extraction kit, then D8S553 and D8S1797 markers used for polymerase chain reaction (PCR). • Results: None of the cases were positive for the two markers D8S553 and D8S1797 on chromosome 8 which were tested in our study. • Conclusion: The possible cause of this finding is that DRS in our patients is more commonly sporadic rather than familial. We recommend study with more cases, other markers, and different chromosomes.