Comprehensive data regarding the epidemiology and prevalence of thalassemia in mainland China are lacking. To assess the prevalence of thalassemia, we performed a meta-analysis including 16 articles published from 1981 to 2015. The overall prevalence of α-thalassemia, β-thalassemia and α + β-thalassemia was 7.88%, 2.21% and 0.48%, respectively. Trends in thalassemia prevalence in mainland China were not steady; a prevalence map based on a geographic information system (GIS) showed that the geographic distribution of thalassemia was highest in the south of China and decreased from south to north. Additionally, the most common α- and β-globin gene mutation was --SEA and CD41/42, respectively. The current study provides valuable information regarding epidemiology and intervention and supports the planning, implementation and management of prevention programmes for public health.

The implications of lncRNAs regarding fetal hemoglobin (HbF) induction in hemoglobin disorders remain poorly understood. In this study, microarray analysis was performed to profile lncRNAs, miRNAs and mRNAs in individuals with hereditary persistence of fetal hemoglobin (HPFH), β-thalassemia carriers with high HbF levels and healthy controls. The results show aberrant expression of 862 lncRNAs, 568 mRNAs and 63 miRNAs in the high-HbF group compared with the control group. Altered NR_001589, NR_120526, T315543, miR-486-3p, miR-19b-1-5p and miR-20a-3p expression was confirmed by quantitative reverse transcription-polymerase chain reaction, and Spearman correlation coefficients revealed significant positive correlations with HbF. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses showed the hematopoietic cell lineage and apoptosis to be most significantly dysregulated in HbF induction. We analyzed coding genes near the lncRNAs and constructed a coding-noncoding co-expression network. Based on the results, lncRNAs likely contribute to increased HbF levels by activating expression of HBE1 and hematopoietic cell lineage-inducible molecules and by inhibiting that of apoptosis-inducible molecules. Finally, through construction of a competing endogenous RNA network, we found that 6 lncRNAs could bind competitively with miR-486-3p, resulting in increased HbF levels. Taken together, our findings provide new insights into the mechanisms of HbF induction and potentially provide new targets for the treatment of β-thalassemia major.

This extensive experience suggests that carrier screening, molecular diagnostics, genetic counselling, and prenatal diagnosis are effective measures to prevent Hb Bart's hydrops fetalis syndrome.