[Gene characteristics and changing trend of neonatal thalassemia in Dongguan, China].

OBJECTIVE: To study the gene distribution characteristics of neonatal thalassemia in Dongguan, China and the changing trend of the gene distribution characteristics of neonates with thalassemia in Dongguan in 2014-2018. METHODS: A retrospective analysis was performed for the data on neonatal thalassemia screening from the Dongguan Neonatal Disease Screening System between January 2014 and December 2018. A total of 616 718 neonates were enrolled who were born in Dongguan. RESULTS: Among the 616 718 neonates, 52 308 were positive for primary screening, 10 366 were recalled, 8 576 underwent genetic diagnosis, and 6 432 were confirmed with thalassemia by genetic diagnosis. The carrying rates of thalassemia genes in 2014-2018 were 5.81%, 5.47%, 5.96%, 6.91%, and 7.90% respectively, and showed an upward trend (P<0.001). The positive rates of neonatal thalassemia screening in 2014-2018 were 9.12%, 8.34%, 7.54%, 8.13%, and 9.32% respectively (P<0.001). The positive rates of genetic diagnosis of neonatal thalassemia in 2014-2018 were 0.89%, 1.11%, 1.24%, 0.90%, and 1.09% respectively (P<0.001). In 2014-2018, 5 098 cases of α-thalassemia were detected, accounting for 79.26% of all cases, and 1 230 cases of ß-thalassemia were detected, accounting for 19.12% of all cases. The detection rate of α-thalassemia was significantly higher than that of ß-thalassemia in each year (P<0.001). In 2014-2018, static α-thalassemia, mild α-thalassemia, and mild ß-thalassemia were the main types observed in neonates. CONCLUSIONS: Most of the neonates with thalassemia have α-thalassemia in Dongguan, with static α-thalassemia and mild α-thalassemia as the main types. The carrying rate of thalassemia genes keeps increasing in neonates in Dongguan, and the prevention and treatment of thalassemia is still challenging.