Objective: To investigate the genotypic and hematological characteristics of β-thalassemia patients and carriers from Henan Province of China.
Methods: Clinical data of the patients and carriers were collected. Results of routine blood test, hemoglobin electrophoresis and genetic testing were retrospectively analyzed.
Results: Of the 83 β-thalassemia patients and carriers, there were 46 females and 37 males, and their mean age was 27.37 ± 14.71, ranging from 5 months to 83 years. A total of 13 types of β-thalassemia alleles (86 alleles in total) were detected, with the most common three including ISV-II-654(C>T) (33.72%), CD41-42(-TTCT) (26.74%) and CD17(A>T) (18.60%). Five rare alleles, including CD8-9(+G), IVS-II-1(G>A), CD42(T>G), and start codons ATG>AGG and ATG>ACG were identified. Among these, HBB: c.128T>G(CD42T>G) was previously unreported in China. Fifteen β-thalassemia genotypes were detected, which included 12 simple heterozygote genotypes (80 cases, 96.40%), 2 double heterozygote genotypes (2 cases, 2.40%) and 1 homozygote genotype (1 case, 1.20%). The main manifestations were mild microcytic hypochromic anemia and raised HbA2. Compared with those with a β+/βN genotype, carriers with a β0/βN genotype have lower mean corpuscular volume (MCV) and mean corpusular hemoglobin (MCH) but higher HbA2 (P<0.05).
Conclusion: β-thalassemia is not rare in Henan Province and its characteristics are different from those in high incidence areas, which deserves close attention. The newly discovered HBB: c.128T>G (CD42T>G) has enriched the spectrum of β-thalassemia mutations in China. Above results will also facilitate genetic counseling and prenatal diagnosis of β-thalassemia in Henan Province.