Vitamin D is an essential micronutrient whose demand is heightened during pregnancy to support the growth of the fetus. Furthermore, the fetus does not produce vitamin D and hence relies exclusively on the supply of maternal vitamin D through the placenta. Vitamin D inadequacy is linked with pregnancy complications and adverse infant outcomes. Hence, early predictive markers of vitamin D inadequacy such as genetic vulnerability are important to both mother and offspring. In this multi-ethnic Asian birth cohort study, we report the first genome-wide association analysis (GWAS) of maternal and fetal vitamin D in circulation. For this, 25-hydroxyvitamin D (25OHD) was measured in the antenatal blood of mothers during mid gestation (n=942), and the cord blood of their offspring at birth (n=812). Around ~7 million single nucleotide polymorphisms (SNPs) were regressed against 25OHD concentrations to identify genetic risk variants. About 41% of mothers had inadequate 25OHD (≤75nmol/L) during pregnancy. Antenatal 25OHD was associated with ethnicity [Malay (Β=-22.32nmol/L, p=2.3×10-26); Indian (Β=-21.85, p=3.1×10-21); reference Chinese], age (Β=0.47/year, p=0.0058), and supplement intake (Β=16.47, p=2.4×10-13). Cord blood 25OHD highly correlated with antenatal vitamin D (r=0.75) and was associated with ethnicity [Malay (Β=-4.44, p=2.2×10-7); Indian (Β=-1.99, p=0.038); reference Chinese]. GWAS analysis identified rs4588, a missense variant in the group-specific component (GC) gene encoding vitamin D binding protein (VDBP), and its defining haplotype, as a risk factor for low antenatal (Β=-8.56/T-allele, p=1.0×10-9) and cord blood vitamin D (Β=-3.22/T-allele, p=1.0×10-8) in all three ethnicities. We also discovered a novel association in a SNP downstream of CYP2J2 (rs10789082), a gene involved in 25-hydroxylation of vitamin D, with vitamin D in pregnant women (Β=-7.68/G-allele, p=1.5×10-8), but not their offspring. As the prevention and early detection of suboptimal vitamin D levels are of profound importance to both mother and offspring's health, the genetic risk variants identified in this study allow risk assessment and precision in early intervention of vitamin D deficiency. ; National Research Foundation (NRF) ; Published version ; This research is supported by the Singapore National Research Foundation under its Translational and Clinical Research (TCR) Flagship Program on Developmental Pathways to Metabolic Disease and administered by the Singapore Ministry of Health's National Medical Research Council (NMRC), Singapore-NMRC/TCR/004-NUS/2008; NMRC/TCR/012-NUHS/2014. KMG is supported by the UK Medical Research Council (MC_UU_12011/4), the National Institute for Health Research (NIHR Senior Investigator (NF-SI-0515-10042) and NIHR Southampton Biomedical Research Centre (IS-BRC-1215-20004)), the European Union (Erasmus+ Programme ImpENSA 598488-EPP-1-2018-1-DE-EPPKA2-CBHE-JP) and the British Heart Foundation (RG/15/17/3174, SP/F/21/150013). Additional funding is provided by the Singapore Institute for Clinical Sciences (SICS), Joint Council Office (JCO) Grant (JCO1431AFG110), and Strategic Positioning Fund (SPF) awarded to NK by the Agency for Science, Technology and Research (A*STAR), Singapore.
In: Gao , Y , Wang , T , Yu , X , Ferrari , R , Hernandez , D G , Nalls , M A , Rohrer , J D , Ramasamy , A , Kwok , J B J , Dobson-Stone , C , Brooks , W S , Schofield , P R , Halliday , G M , Hodges , J R , Piguet , O , Bartley , L , Thompson , E , Haan , E , Hernández , I , Ruiz , A , Boada , M , Borroni , B , Padovani , A , Cruchaga , C , Cairns , N J , Benussi , L , Binetti , G , Ghidoni , R , Forloni , G , Albani , D , Galimberti , D , Fenoglio , C , Serpente , M , Scarpini , E , Clarimón , J , Lleó , A , Blesa , R , Waldö , M L , Nilsson , K , Nilsson , C , Mackenzie , I R A , Hsiung , G Y R , Mann , D M A , Grafman , J , Morris , C M , Attems , J , Griffiths , T D , Rowe , J B , Nielsen , J E , Hjermind , L E & International FTD-Genomics Consortium (IFGC) 2020 , ' Mendelian randomization implies no direct causal association between leukocyte telomere length and amyotrophic lateral sclerosis ' , Scientific Reports , vol. 10 , no. 1 , 12184 . https://doi.org/10.1038/s41598-020-68848-9
We employed Mendelian randomization (MR) to evaluate the causal relationship between leukocyte telomere length (LTL) and amyotrophic lateral sclerosis (ALS) with summary statistics from genome-wide association studies (n = ~ 38,000 for LTL and ~ 81,000 for ALS in the European population; n = ~ 23,000 for LTL and ~ 4,100 for ALS in the Asian population). We further evaluated mediation roles of lipids in the pathway from LTL to ALS. The odds ratio per standard deviation decrease of LTL on ALS was 1.10 (95% CI 0.93–1.31, p = 0.274) in the European population and 0.75 (95% CI 0.53–1.07, p = 0.116) in the Asian population. This null association was also detected between LTL and frontotemporal dementia in the European population. However, we found that an indirect effect of LTL on ALS might be mediated by low density lipoprotein (LDL) or total cholesterol (TC) in the European population. These results were robust against extensive sensitivity analyses. Overall, our MR study did not support the direct causal association between LTL and the ALS risk in neither population, but provided suggestive evidence for the mediation role of LDL or TC on the influence of LTL and ALS in the European population.
In: Gao , Y , Wang , T , Yu , X , Ferrari , R , Hernandez , D G , Nalls , M A , Rohrer , J D , Ramasamy , A , Kwok , J B J , Dobson-Stone , C , Brooks , W S , Schofield , P R , Halliday , G M , Hodges , J R , Piguet , O , Bartley , L , Thompson , E , Haan , E , Hernández , I , Ruiz , A , Boada , M , Borroni , B , Padovani , A , Cruchaga , C , Cairns , N J , Benussi , L , Binetti , G , Ghidoni , R , Forloni , G , Albani , D , Galimberti , D , Fenoglio , C , Serpente , M , Scarpini , E , Clarimón , J , Lleó , A , Blesa , R , Waldö , M L , Nilsson , K , Nilsson , C , Mackenzie , I R A , Hsiung , G Y R , Mann , D M A , Grafman , J , Morris , C M , Attems , J , Griffiths , T D , McKeith , I G , Thomas , A J , Pietrini , P , Huey , E D , Wassermann , E M , Baborie , A , Jaros , E , Tierney , M C , Pastor , P , Razquin , C , Ortega-Cubero , S , Alonso , E , Perneczky , R , Diehl-Schmid , J , Alexopoulos , P , Kurz , A , Rainero , I , Rubino , E , Pinessi , L , Rogaeva , E , George-Hyslop , P S , Rossi , G , Tagliavini , F , Giaccone , G , Rowe , J B , Schlachetzki , J C M , Uphill , J , Collinge , J , Mead , S , Danek , A , Van Deerlin , V M , Grossman , M , Trojanowski , J Q , van der Zee , J , Cruts , M , Van Broeckhoven , C , Cappa , S F , Leber , I , Hannequin , D , Golfier , V , Vercelletto , M , Brice , A , Nacmias , B , Sorbi , S , Bagnoli , S , Piaceri , I , Nielsen , J E , Hjermind , L E , Riemenschneider , M , Mayhaus , M , Ibach , B , Gasparoni , G , Pichler , S , Gu , W , Rossor , M N , Fox , N C , Warren , J D , Spillantini , M G , Morris , H R , Rizzu , P , Heutink , P , Snowden , J S , Rollinson , S , Richardson , A , Gerhard , A , Bruni , A C , Maletta , R , Frangipane , F , Cupidi , C , Bernardi , L , Anfossi , M , Gallo , M , Conidi , M E , Smirne , N , Rademakers , R , Baker , M , Dickson , D W , Graff-Radford , N R , Petersen , R C , Knopman , D , Josephs , K A , Boeve , B F , Parisi , J E , Seeley , W W , Miller , B L , Karydas , A M , Rosen , H , van Swieten , J C , Dopper , E G P , Seelaar , H , Pijnenburg , Y A L , Scheltens , P , Logroscino , G , Capozzo , R , Novelli , V , Puca , A A , Franceschi , M , Postiglione , A , Milan , G , Sorrentino , P , Kristiansen , M , Chiang , H H , Graff , C , Pasquier , F , Rollin , A , Deramecourt , V , Lebouvier , T , Kapogiannis , D , Ferrucci , L , Pickering-Brown , S , Singleton , A B , Hardy , J , Momeni , P , Zhao , H , Zeng , P & International FTD-Genomics Consortium (IFGC) 2020 , ' Mendelian randomization implies no direct causal association between leukocyte telomere length and amyotrophic lateral sclerosis ' , Scientific Reports , vol. 10 , no. 1 , 12184 . https://doi.org/10.1038/s41598-020-68848-9
We employed Mendelian randomization (MR) to evaluate the causal relationship between leukocyte telomere length (LTL) and amyotrophic lateral sclerosis (ALS) with summary statistics from genome-wide association studies (n = ~ 38,000 for LTL and ~ 81,000 for ALS in the European population; n = ~ 23,000 for LTL and ~ 4,100 for ALS in the Asian population). We further evaluated mediation roles of lipids in the pathway from LTL to ALS. The odds ratio per standard deviation decrease of LTL on ALS was 1.10 (95% CI 0.93–1.31, p = 0.274) in the European population and 0.75 (95% CI 0.53–1.07, p = 0.116) in the Asian population. This null association was also detected between LTL and frontotemporal dementia in the European population. However, we found that an indirect effect of LTL on ALS might be mediated by low density lipoprotein (LDL) or total cholesterol (TC) in the European population. These results were robust against extensive sensitivity analyses. Overall, our MR study did not support the direct causal association between LTL and the ALS risk in neither population, but provided suggestive evidence for the mediation role of LDL or TC on the influence of LTL and ALS in the European population.