Hyperphenylalaninemia, BH4-Deficient, B

Early Check provides voluntary screening of newborns for a selected panel of conditions. The study has three main objectives: 1) develop and implement an approach to identify affected infants, 2) address the impact on infants and families who screen positive, and 3) evaluate the Early Check program. The Early Check screening will lead to earlier identification of newborns with rare health conditions in addition to providing important data on the implementation of this model program. Early diagnosis may result in health and development benefits for the newborns. Infants who have newborn screening in North Carolina will be eligible to participate, equating to over 120,000 eligible infants a year. Over 95% of participants are expected to screen negative. Newborns who screen positive and their parents are invited to additional research activities and services. Parents can enroll eligible newborns on the Early Check electronic Research Portal. Screening tests are conducted on residual blood from existing newborn screening dried blood spots. Confirmatory testing is provided free-of-charge for infants who screen positive, and carrier testing is provided to mothers of infants with fragile X. Affected newborns have a physical and developmental evaluation. Their parents have genetic counseling and are invited to participate in surveys and interviews. Ongoing evaluation of the program includes additional parent interviews.

The purpose of this study is to identify the dose of Kuvan needed to normalize the levels of tetrahydrobiopterin (BH4) in patients with a Guanosine Triphosphate Cyclohydrolase (GTPCH) deficiency and to asses the potential impact of oral Kuvan on mood and function in individuals with GTPCH deficiency who may be experiencing symptoms of anxiety, depression, fatigue, trouble concentrating, or memory loss. This will be a phase one study. The investigators will monitor patients over a period of three to six months while on the medication. Medication levels will be monitored by measuring the BH4 levels in cerebral spinal fluid (CSF). Patients will undergo a baseline lumbar puncture and two follow-up lumbar punctures for this purpose. The investigators will also monitor emotional function and motor function.