Abstract
β-Carotene15,15'-monooxygenase (BCMO1) is a key enzyme in the metabolism of provitamin A carotinoids. This enzyme cleaves the center of dietary vitamin A carotinoids including β-carotene, α-carotene, and β-cryptoxanthin to form retinal. Retinal is produced at the first step of the conversion of provitamin A carotinoids to vitamin A. Recently, a lot of studies to evaluate the rate of β-carotene conversion using biomarkers have been performed. The rate of the conversion of provitamin A carotinoids to vitaminA is known to be highly variable in human population. On the other hand, single nucleotide polymorphisms (SNPs) for BCMO1 which exist in human genome have been analyzed and the existence of 3,483 SNPs in BCMO1 gene has been identified. Several reports have indicated the association between these SNPs and β-carotene conversion. The first report showed that T170M, a SNP of BCMO1 gene with amino acid substitution, was related to hypercarotenemia and hypovitaminosis A in the patients with carotenosis. Furthermore, it was reported that SNPs related to β-carotene conversion in the exon region, which caused amino acid substitution, were found in human population. Recently, a role of the SNP of BCMO1 gene present in the gene promoter region has been reported. In this mini review, we have focused on the relation between SNPs for BCMO1 and the bioavailability of plant-based provitamin A.
