[Analysis of the phenotype-genotype relationship of hemoglobin Q-Thailand in Guangxi].

Objective: To investigate the hematological and molecular characteristics of hemoglobin Q-Thailand in Guangxi, so as to provide reference data for hemoglobinopathy screening.

Methods: A total of 51088 samples were screened by capillary electrophoresis. Samples suspected with Hb Q-Thailand were processed with blood cell count and DNA sequencing. Gap-PCR and PCR-reverse dot blotting were used for the detection of common mutations of alpha and beta thalassemia.

Results: The carrier rate of Hb Q-Thailand in Guangxi was 0.06%. The hematological phenotype index(HGB, MCV, MCH, Hb Q-Thailand, Hb A2, Hb QA2) of 28 Hb Q-Thailand heterozygous samples were (125.60±22.30) g/L, (78.22±4.81) fl, (25.79±2.14) pg, (27.37±2.72)%, (1.89±0.22)%, (0.69±0.16)%, respectively, and of 2 Hb Q-Thailand heterozygous combined with beta-thalassemia samples were (125.00±18.39) g/L, (69.65±5.02) fl, (22.00±0.0) pg, (14.80±0.71)%, (4.45±0.07)%, (0.95±0.71)%, respectively. A statistical difference was found in hematological phenotype index between the two groups except HGB (P<0.05).

Conclusion: In Guangxi, the detected Hb Q-Thailands were mainly heterozygous. Part of Hb Q-Thailand heterozygotes had normal red blood cell parameters, but can still be detected by hemoglobin electrophoresis. When combined with other types of thalassemia, these heterozygotes may still exhibit reduced MCV and MCH or various degrees of anemia.