Background and Objective: Alpha thalassemia is one of the most common hemoglobin
disorders. Some combination of alpha globin gene mutations may cause HbH disease with severe
anemia or intermediate thalassemia. genotype common deletions are routinely tested for
suspicious alpha thalassemia couples but because of lack of information about the nature and
frequency of point mutations and higher expenosor of sequencing, less attention was paid to
them. This study was done to determine the prevalence of common point mutations of alpha
globin gene in Babol, Iran.
Materials and Methods: This descriptive study was carried out on DNA of 153 adult suspected
to α-thalasemia with deleted α- golobolin gene referred to genetic laboratory in Babol, Iran
during 2005-09. a1 and a2 genes were amplified by using specific biotinilated primers by PCR
method. PCR products were assayed using 11 specific probs corresponding to common point
mutations in alpha gene (C19, IVSI (-5nt), C59, Hb constant spring, Hb Icaria, Hb seal Rock,
IVSI (148), C14, poly A (-2bp), poly A2, Poly A1) and fixed on byodine C membrabe.
Hybridization between the probes and PCR products was visualized after a colorimetric reaction
using of conjugated streptavidin peroxidase and TMB (tetra methyle Benzidine) and H2O2.
Results: The prevalence of point mutations in poly A2, 5nt, Hb constant spring and
poly A1 were 28.75%, 14.38%, 7.84% and 2.61%, respectively.
Conclusion: Point mutation in alpha globin genes was detected in %53.60 out of 153 adults
suspected with alpha thalassemia without common deletion mutations. |