Phenylalanine supplementation in Tyrosinemia type 1
Research type
Research Study
Full title
The effect of phenylalanine supplementation on metabolic control in Tyrosinemia type 1 patients
IRAS ID
216139
Contact name
Saikat Santra
Contact email
Sponsor organisation
University Medical Center Groningen
Duration of Study in the UK
1 years, 0 months, 0 days
Research summary
Hereditary Tyrosinemia Type 1 (HT1) patients usually present with liver dysfunction and/or renal tubular dysfunction with rickets early in life. After the introduction of 2-(2-nitro-4-trifluoro-methylbenzoyl)-1,3-cyclohexanedione (NTBC), problems resolved and life expectancy greatly increased. However, due to NTBC, which blocks the conversion of tyrosine at an earlier step, tyrosine concentrations increase, and therefore dietary restrictment of tyrosine and its precursor phenylalanine is needed again. Recently, some research articles report about low phenylalanine concentrations in HT1 and a possible correlation between these low phenylalanine concentrations and clinical problems such as eczema and an impaired cognitive development. This makes phenylalanine supplementation necessary despite possible conversion to tyrosine and the resulting increase in tyrosine.
Previous research has also shown a consistent diurnal variation of phenylalanine, with extremely low phenylalanine concentrations early in the afternoon. This consistent diurnal variation and increase in tyrosine concentrations suggest that studies examining the optimal dose of phenylalanine supplementation (a specific food for medical purposes) is necessary.REC name
West Midlands - South Birmingham Research Ethics Committee
REC reference
17/WM/0114
Date of REC Opinion
3 Jul 2017
REC opinion
Further Information Favourable Opinion