However, using PSV cutoff values, only 4 patients could be classified as having “abnormal” PSV as compared to 7 patients who qualified for being “abnormal” by the standard TAMMV criteria used in the pivotal STOP trial.[11] Our observations could have been biased due to the small sample size or other factors like milder disease in Indian SCD patients, as their Beta-globin mutation is on chromosomes with Saudi Arabia/India beta gene haplotype.[27,28]. This evidence concerns the gene HBB and Schnyder corneal dystrophy.