Inversion 22 molecular screening in Egyptian hemophilic cohort

Abstract

BackgroundHemophilia A (HA) is an X-linked bleeding disorder caused by the absence or reduced activity of coagulation factor VIII. Inversion of intron 22 (inv22) is detected in 50% of cases of severe HA and is known as a major risk factor for inhibitor formation. AimThe aim was to study inv22 prevalence among the Egyptian hemophilic children and the genetic association of inv22 with the disease severity and inhibitor formation. We also aimed to implement a faster and more accurate molecular technology to facilitate inv22 detection in the genetic diagnosis of hemophilic patients. MethodsThis is a cross sectional study performed on 60 hemophilic boys. DNA samples were tested for inv22 by coupled long distance polymerase chain reaction with Syber green detection system using Real Time PCR technology. ResultsOut of the 60 hemophilic boys, 24 patients harbored inv22. All of them presented with severe HA, where allof them had joint bleeds [OR (95% CI): 1.9 (1.5–2.5); p 0.008] Inv 22 was not detected in patients having mild or moderate HA [OR (95% CI): 2.5 (1.71 – –3.65); p 0.001]. . Moreover, there was no significant correlation between the occurrence of inv. 22 and inhibitor formation (p = 0.5). ConclusionThere is a significant direct correlation between Inv22 and the severity of the disease, however, there was no significant correlation between Inv22 occurrence and inhibitor formation. Our modified PCR protocol that couples LD-PCR with Syber green detection system using Real Time PCR technology is more rapid and convenient for Inv22 detection in genetic diagnosis of HA. It could be applied clinically in the Pre-genetic diagnosis in the future.