[Genotype and Phenotype of α-Thalassemia Fusion Gene in Huadu District of Guangzhou, Guangdong Province of China].

OBJECTIVE: To explore the carrier rate, genotype and phenotype of α-thalassemia fusion gene in Huadu district of Guangzhou, Guangdong province of China, and provide data reference for the prevention and control of thalassemia. METHODS: A total of 10 769 samples who were screened for thalassemia in Maternal and Child Health Hospital of Huadu District from July 2019 to November 2020 were analyzed retrospectively. Blood cell analysis and hemoglobin (Hb) electrophoresis were performed. Thalassemia genes were analyzed by gap-PCR and PCR-reverse dot blot hybridization (PCR-RDB). RESULTS: A total of 9 cases with α-thalassemia fusion gene were detected in 10 769 samples (0.08%). There were 7 cases with fusion gene heterozygote, 1 case with compound of α-thalassemia fusion gene and Hb G-Honolulu, 1 case with compound of α-thalassemia fusion gene and Hb QS. The MCV results of 4 samples of blood cell analysis were within the reference range, the Hb A2 value of 1 case was decreased, and there were no other abnormalities found. CONCLUSION: The α-thalassemia fusion gene is common in Huadu district of Guangzhou, and heterozygotes are more common, and current screening methods easily lead to misdiagnosis.

[Evaluation of direct digital radiography image quality in dentistry].

PURPOSE: To evaluate the quality of direct digital radiograph according to its application in dentistry. METHODS: 1195 patients with dental caries, periodontal diseases, periapical diseases, trauma of teeth or hypodontia were tested with Trophy elitys Radio Visio Graphy(RVG) and the quality of the tests was evaluated at four levels. RESULTS: It was convenient to operate RVG and easy to save the images, which reduced the amount of X-rays. 1587 pictures were taken, among which 92.3% was at level I, 6.3% was at level II,1.14% was at level III and level IV. CONCLUSIONS: The quality of the images at different positions is good, which can meet the requirement for clinical diagnosis. However, the radiography receptor should be improved for better images.