YIN-HSIU CHIENChiang S.-C.Huang A.Lin J.-M.YEN-NAN CHIUChou S.-P.Chu S.-Y.Wang T.-R.WUH-LIANG HWU2020-12-162020-12-1620010141-8955https://www.scopus.com/inward/record.uri?eid=2-s2.0-0035719532&doi=10.1023%2fA%3a1013984022994&partnerID=40&md5=9a72e518f7b78bb3477c27519691240dhttps://scholars.lib.ntu.edu.tw/handle/123456789/526069Ten cases of tetrahydrobiopterin (BH4) deficiency were identified in 1 337 490 newborns screened in a Chinese population in Taiwan. The high incidence of BH4 deficiency in the Taiwanese population may be explained by a founder effect, since all of the patients revealed 6-pyruvoyltetrahydropterin synthase gene mutations, and grouping N52S and P87S mutations together constituted 88.9% of the disease alleles. BH4 supplementation with restriction of high-protein foods gave control of plasma phenylalanine within normal range, and levadopa itself prevented seizure. However, the average intelligence quotient (IQ) score of these patients was only 76 ± 14 (56-98). Statistically, the age of starting medication, including 5-hydroxytrytophan (5-HTP), was inversely correlated to IQ scores of these patients. We suggest the combination of BH4, levodopa and 5-HTP as the standard protocol to commence the treatment of BH4 deficiency as early as possible, although prenatal brain damage could have existed.[SDGs]SDG35 hydroxytryptophan; 6 pyruvoyltetrahydropterin synthase; levodopa; phenylalanine; tetrahydrobiopterin; allele; amino acid blood level; article; brain injury; child; Chinese; clinical article; clinical protocol; controlled study; correlation function; embryo; enzyme deficiency; founder effect; gene mutation; human; incidence; intelligence quotient; newborn screening; population research; prenatal disorder; protein restriction; seizure; statistical analysis; Taiwan; treatment outcome; 5-Hydroxytryptophan; Base Sequence; Biopterin; DNA Mutational Analysis; Founder Effect; Humans; Infant, Newborn; Intelligence; Levodopa; Mutation; Neonatal Screening; Phenylalanine; Phenylketonurias; Phosphorus-Oxygen Lyases; Taiwan; Treatment Outcomejournal article10.1023/A:1013984022994119163142-s2.0-0035719532