ABSTRACT
A total of 1 295 516 dried blood spots were collected from newborns in Hainan Province from 2007 to 2019 who participated in the screening of neonatal diseases, and 43 cases of hyperphenylalaninemia were diagnosed. Among the 43 cases, 8 cases were confirmed to have tetrahydrobiopterin deficiency (4 males and 4 females). The incidence of tetrahydrobiopterin deficiency among newborns in Hainan Province was 6.2/1 million. Six mutations in the PTS gene were detected among 7 cases; the mutations were as follows: c.317C>T, c.286G>A, c.259C>T, c.155A>G, c.84+291A>G and c.83+1777T>G. A homozygous mutation at c.41T>C site of QDPR gene was detected in one case. Overall, it's found that the incidence of tetrahydrobiopterin deficiency in newborn populations in Hainan Province is low, and PTS gene mutations account for the largest proportion of cases of tetrahydrobiopterin deficiency within the study population.
