Frequency of Intron 22 Inversion in Severe Hemophilia A Patients.

Objective: The aim of our study was to find the frequency of Intron 22 inversion (Inv22) in severe hemophilia A (HA) patients and to evaluate the association between Inv22 and FVIII inhibitor formation.

Method: Data analysis was carried out on IBM SPSS Statistics Version 23.00 (IBM Corp, Armonk, NY). Descriptive statistics were applied to measure the frequencies, percentages, and mean ± SD of the clinical and general history of HA patients, including age, family history, inhibitor status, intron22 inversion, and FVIII levels. Chi-square was applied to evaluate the association between Inv22 and F8 inhibitor formation.

Results: A total of 62 HA patients were enrolled in the study with mean±SD age of (14.39±13.2) years. A family history of HA was observed in 36 (58.1%) patients. Out of 62 patients, 28(45.2%) were reported as Inv22 positive while inhibitor status was observed as positive in three (4.83%) patients. However, an insignificant association was observed between the inhibitor and Inv22 positive patients with a p-value=0.443.

Conclusion: In our study, Inv22 was found to be the major cause of severe HA in our patients, i.e., 45.1%. However, no significant relation was computed between Inv22 and inhibitor formation.