Haematological Data in 312 Cases of β‐Thalassaemia Trait in Thailand

Abstract

Summary. The haematological data are presented in 312 individuals of Thai or Chinese extraction with the high A 2 β‐thalassaemia trait. The mean haemoglobin concentrations were 12.1 g% among males and 10.8 g% among eemalcs; 54% of the subjects were not anaemic and all were asymptomatic. Low MCV, MCH and MCHC values were found in 67%, 81% and 6% respectively; erythrocytosis was detected in 34%. Variable hypochromia and microcytosis were usually present, but leptocytosis and red cell basophilic stippling were often absent. Decreased red cell osmotic fragility was always detected. Fifteen cases were found to have normal red cell morphology and 17 normal red cell osmotic fragility. The reticulocyte counts, although ranged up to 12%, were normal in the majority. The serum iron levels and unsaturated iron binding capacity were normal except in 11% of the cases where the scrum iron levels were lower than 50 μg%. Haemoglobin A 2 levels varied from 3.4 to 7.8% with a normal distribution and a mean of 5.2%. Haemoglobin F levels varied from o to 7.8% with 58% elevated values. Analysis of variance revealed intrafamilial segregation of both haemoglobin A 2 and haemoglobin F levels. The literature is reviewed and findings are compared. Copyright © 1973, Wiley Blackwell. All rights reserved