[Retrospective Analysis of Hematological Phenotypes in Patients with Gene Mutation and Deletion α-Thalassemia]

To explore the differences between hematological phenotypes of patients with different genotypes in gene mutations and deletion α- thalassemia.

By screening the α- thalassemia gene test results in the First Affiliated Hospital, Sun Yat-Sen University from January 2015 to April 2020, the patients with mutation and deletion α- thalassemia were obtained, then the differences between hematological phenotypes of patients with different genotypes were analyzed.

There were 96 patients with mutation combined with deletion α- thalassemia from the results of 24 054 α- thalassemia patients screened out, including 79 patients with non-deletion Hb H disease (α^Tα/--^SEA) and 17 patients with mild α- thalassemia (α^Tα/-α), the incidence was 0.42%. Except the number of red blood cells (RBC) and mean corpuscular volume (MCV), the hemoglobin (Hb) concentration, hematocrit (Ht), average red blood cell hemoglobin concentration (MCHC), average red blood cell hemoglobin amount (MCH), average red blood cell volume (MCV) of the patients with α^Tα/--SEA genotype were significantly lower than those with α^Tα/-α genotype. The Hb of the patients with α^CSα/--^SEA and α^QSα/--^SEA genotype was (86±20)g/L and (84±9)g/L, respectirely, which was significantly lower than (114±16) g/L of α^WSα/--^SEA genotype (P<0.05); The MCHC of patients with α^CSα/--^SEA and α^QSα/--^SEA genotype was (278.8±8.5) g/L and (282.1±21.1)g/L, respectirely, which was also significantly lower than (315.4±19.5) g/L of α^WSα/--^SEA genotype (P<0.05); There was no significant difference between the patients with α^CSα/--^SEA and α^QSα/--^SEA genotype in hematological phenotypes. Except MCH and MCV, there was no significant differences between the patients with α^WSα/--^SEA and α^Tα/-α genotype in RBC, Hb, and Ht. The result of Hb A₂ was (2.3±0.9)% for only 27 patients who performed electrophoretic analysis. There was no significant difference between the patients with α^Tα/--^SEA and α^Tα/-α genotype in Hb A₂, aslo among 3 types of the patients with α^Tα/--^SEA genotype.

The hematological phenotype changes caused by α^WSα/--^SEA genotype are similar to those of mild α- thalassemia, and both of them are significantly lighter than those patients with α^CSα/--^SEA and α^QSα/--^SEA genotype.