QDPR gene mutation and clinical follow-up in Chinese patients with dihydropteridine reductase deficiency.

Background: This study aimed to investigate the mutation spectrum of the QDPR gene, to determine the effect of mutations on dihydropteridine reductase (DHPR) structure/function, to discuss the potential genotypephenotype correlation, and to evaluate the clinical outcome of Chinese patients after treatment.

Methods: Nine DHPR-deficient patients were enrolled in this study and seven of them underwent neonatal screening. QDPR gene mutations were analyzed and confirmed by routine methods.

[Application of enzyme assay and gene analysis in the prenatal diagnosis for a family with glycogen storage disease type II].

Objective: To carry out prenatal diagnosis for a glycogen storage disease type II (GSD II ) affected family.

Methods: The acid-α -glucosidase (GAA) activity was measured in whole leukocytes and cultured amniocytes with 4-methylumbelliferyl-α -D-glucopyranoside as substrate and with acarbose as inhibitor. The coding regions of GAA gene were amplified by polymerase chain reaction and analyzed by direct DNA sequencing.

[The investigation of differential diagnostic development and incidence of tetrahydrobiopterin deficiency].

Objective: To investigate the development of differential diagnosis of tetrahydrobiopterin (BH4) deficiency among patients with hyperphenylalaninemia (HPA) in provinces or cities of China and to investigate the incidence of BH4 deficiency.

Methods: Of the thirteen hundreds and ninety-two patients with HPA received, the differential diagnosis for BH4 deficiency during 1993 - 2007 were enrolled in this study. Of which, 591 patients came from outpatient and 801 patients' samples from other provinces or cities were sent to author's laboratory to investigate the case number of differential diagnosis for BH4 deficiency in provinces or cities of China according to the data from both outpatient case histories and laboratory as to investigating the development of differential diagnosis in the whole country.

[Diagnosis, treatment and gene mutation analysis of the first case with dihydropteridine reductase deficiency in the mainland of China].

Objective: The 6-pyruvoyl-tetrahydropterin synthase (PTPS) deficiency is the most common type of tetrahydrobiopterin (BH4) deficiency. The reported patients with BH4 deficiency are all PTPS deficient found in the mainland of China previously. The activity of dihydropteridine reductase in BH4 metabolism has been determined for 902 patients with hyperphenylalaninemia in the authors' laboratory since 2003.

[Diagnosis, treatment and long-term following up of 223 patients with hyperphenylalaninemia detected by neonatal screening programs].

Objective: To investigate the incidence of hyperphenylalaninemia (HPA) caused by different etiologic factors in China and the relationship between the phenylalanine and mental development of patients with HPAs who were diagnosed by neonatal screening and early treated.

Methods: Two hundred and twenty-three patients with HPA detected by neonatal screening programs were refered to us at the age of (41 +/- 27) days after birth. The differential diagnosis was performed by BH(4) (20 mg/kg) loading test, urinary pterin analysis and dihydropteridine reductase (DHPR) activity determination respectively.

[Screening for tetrahydrobiopterin metabolic disorders and related gene analysis among the patients with motor disturbance and mental retardation].

Objective: To study the incidence of various enzyme deficiency in tetrahydrobiopterin (BH4) metabolism and the related gene mutation among the patients with motor disturbance and mental retardation.

Methods: One hundred patients with unknown motor disturbance and mental retardation were referred to this study. All patients were performed by phenylalanine (Phe) and BH4 loading test, urinary pterin analysis and dihydropteridine reductase (DHPR) activity.