Poster Presentation Indian Ocean Rim Laboratory Haematology Congress 2019

Alpha thalassemia genotypes distribution among Khuzestan province people referred to Nor genetic laboratory (#68)

Mehri Ehtiati 1 , Mohammad Ali Jalali Far 2 3 , Najmaldin Saki 2 , Javad Mohammadi Asl 2 , Mina Ebrahimi 2 , Mehdi Ehtiati 4 , Mohammod Ehtiati 5
  1. Shahid Beheshti University of Medical Sciences, Tehran, Iran
  2. Thalassemia& Hemoglobinopathy Research Center, Health Research Institute. Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
  3. High Institute for Research and Education in Transfusion Medicine, Tehran, Iran
  4. Shahid Beheshti Institute, Sampaad, Ahwaz, Iran
  5. University of Science and Technology, Tehran, Iran

Thalassemia is the most frequent genetically disorders of hemoglobin worldwide. Alpha thalassemia caused by genetically deletion or mutation that affect Alpha chain synthesis. It is estimated that Alpa thalassemia affected between 1% and 98% throughout the tropics and subtropics. The clinical manifestations of Alpha thalassemia are depending on the genotype varied and are less than beta thalassemia. The coinheritance or existence of alpha thalassemia with beta and/or other hemoglobinopathies interfere with diagnosis. Determination of Alpha thalassemia genotypes helps us in prevention of misdiagnosis.

Descriptive study was included 292 people that referred to Nor Genetic Laboratory. Peripheral venous blood (2.5ml) was collected into an EDTA-anticoagulated tube. Peripheral blood counts and red blood cell indices were determined using Sysmex automated blood cell analyzer (XN-1000TM). Hb electrophoresis was used to determine the concentration of Hb A, A2 and F for all individuals. For deletion in Alpha chains the gap-polymerase chain reaction (Gap-PCR) technique were used and DNA sequencing used to detect other forms of alpha thalassemia genotypes.

Our findings showed that the population was included 49 % male, 49.7 % and the other was fetus or neonates. The Hemoglobin, MCV, MCH of our population was 130.1±30.6 gr/L, 75.8±12.6 fL and 24.4±4.8 gr respectively. The percent of hemoglobin A2 and F was 2.5±1.4 and 0.6±1.8. The 67.4 % of first locus of Alpha gene was affected and the prevalent genotypes among our population in that locus was -3.7, codon75, T and codon 85 with 41.9 %,8.1 ,5 % and 2.7 %. The codon 17,20, 22 and 24 with 0.4 % was the less prevalent genotypes.

According to our findings except -3.7 deletion the other genotypes prevalence different from other regions in our country and other studies. Due to the effect of the Alpha genotypes special the point mutational on laboratory and clinical manifestation, the Alpha genotyping is recommended in prenatal and premarital screening for thalassemia and hemoglobinopathies.