Pigmentation of the Skin Due to Vitamin a Deficiency

Identifying genes associated with genetic control of color polymorphism in the pearl oysterPinctada margaritiferavar.cumingii(Linnaeus 1758) using a comparative whole genome pool‐sequencing approach

“…In addition to the previously identified heme pathway, our genome‐wide study highlighted a new pigmentation pathway not previously identified as involved in the red phenotype: the carotenoid pathway. Carotenoids are well‐known red, brown, and yellow pigments (Hornero‐Méndez et al, 2000 ; Lado et al, 2015 ; Tolmach & Graham, 1942 ). A SNP was located in the 5′ regions of the β, β ‐Carotene 15,15′‐dioxygenase gene (BCO1) and has a higher frequency in the red phenotype than others.…”

“…This SNP significantly changed the tertiary conformation of the protein by shortening an alpha helix and creating a new beta‐strand at the modified amino acid position, which suggests a possible impact on its functionality. SNPs affecting BCO1, CYP26A1, CYP2C8, CYP3A29, and UGT could affect concentrations of circulating carotenoids by modifying the degradation of β‐carotene molecules into all‐trans‐retinoic acids, leading to an accumulation of β‐carotene that would have to be excreted/degraded into pigmented carotenoids forms (Biesalski et al, 2007 ; Chichili et al, 2005 ; Hill & Johnson, 2012 ; Hornero‐Méndez et al, 2000 ; Lado et al, 2015 ; Lietz et al, 2012 ; Nadin & Murray, 1999 ; Naveed et al, 2018 ; Tolmach & Graham, 1942 ). Recently, retinol and retinoic genes have been confirmed to be associated with the shell color of C. gigas in the orange and black phenotype (Li et al, 2022 ).…”

“…For each protein, the information for one SNP is given as an example, with the name of this SNP (scaffold number and position of the SNP), the reference (R) and alternative (A) allele, their impact, and the number of transcripts bearing SNPs coding the same protein. molecules into all-trans-retinoic acids, leading to an accumulation of β-carotene that would have to be excreted/degraded into pigmented carotenoids forms (Biesalski et al, 2007;Chichili et al, 2005;Hill & Johnson, 2012;Hornero-Méndez et al, 2000;Lado et al, 2015;Lietz et al, 2012;Nadin & Murray, 1999;Naveed et al, 2018;Tolmach & Graham, 1942). Recently, retinol and retinoic genes have been confirmed to be associated with the shell color of C. gigas in the orange and black phenotype (Li et al, 2022).…”