https://nova.newcastle.edu.au/vital/access/ /manager/Index ${session.getAttribute("locale")} 5 https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:43197 n = 649) Australian cross-sectional study population. Genetic analysis was used to score vitamin D- and folate-related gene polymorphisms (n = 22), along with two pigmentation gene variants (IRF4-rs12203592/HERC2-rs12913832). Red cell folate and vitamin D₃ were measured by immunoassay and HPLC, respectively. Results: i. Ultraviolet radiation (UVR) and pigmentation genes interact to modify blood vitamin levels; Light skin IRF4-TT genotype has greatest folate loss while light skin HERC2-GG genotype has greatest vitamin D₃ synthesis (reflected in both TOMS and seasonal data). ii. UV-wavelength exhibits a dose–response relationship in folate loss within light skin IRF4-TT genotype (305 > 310 > 324 > 380 nm). Significant vitamin D₃ photosynthesis only occurs within light skin HERC2-GG genotype, and is maximal at 305 nm. iii. Three dietary antioxidants (vitamins C, E, and β-carotene) interact with UVR and pigmentation genes preventing oxidative loss of labile reduced folate vitamers, with greatest benefit in light skin IRF4-TT subjects. The putative photosensitiser, riboflavin, did not sensitize red cell folate to UVR and actually afforded protection. iv. Four genes (5xSNPs) influenced blood vitamin levels when stratified by pigmentation genotype; MTHFR-rs1801133/rs1801131, TS-rs34489327, CYP24A-rs17216707, and VDR-ApaI-rs7975232. v. Lightest IRF4-TT/darkest HERC2-AA genotype combination (greatest folate loss/lowest vitamin D₃ synthesis) has 0% occurrence. The opposing, commonest (39%) compound genotype (darkest IRF4-CC/lightest HERC2-GG) permits least folate loss and greatest synthesis of vitamin D₃. Conclusion: New biophysical evidence supports the vitamin D-folate hypothesis for evolution of skin pigmentation.]]> Wed 14 Sep 2022 09:33:28 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:53966 4 and DNA damage repair), with the relevance of this to the UV sensitivity of folate and UV photosynthesis of vitamin D explained in detail, including the relevance of these vitamins to reproductive success. It explores whether we might be able to predict vitamin‐related gene polymorphisms that pivot metabolism to the prevailing UVR exposome within the vitamin D‐folate evolutionary hypothesis context. This is discussed in terms of a primary adaptive phenotype (pigmentation/depigmentation), a secondary adaptive phenotype (flexible metabolic phenotype based on vitamin‐related gene polymorphism profile), and a tertiary adaptive strategy (dietary anti‐oxidants to support the secondary adaptive phenotype). Finally, alternative evolutionary models for pigmentation are discussed, as are challenges to future research in this area.]]> Tue 23 Jan 2024 14:38:17 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:53494 Thu 30 Nov 2023 15:44:11 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:6952 Sat 24 Mar 2018 10:46:30 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:1033 Sat 24 Mar 2018 08:31:54 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:1162 Sat 24 Mar 2018 08:28:43 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:1459 Sat 24 Mar 2018 08:28:08 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:18247 Sat 24 Mar 2018 08:04:50 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:21346 Sat 24 Mar 2018 07:51:24 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:333 Sat 24 Mar 2018 07:42:40 AEDT ]]>