{{Rsnum
|rsid=12785878
|Gene=NADSYN1
|Chromosome=11
|position=71456403
|Orientation=plus
|GMAF=0.4715
|Assembly=GRCh38
|GenomeBuild=38.1
|dbSNPBuild=141
|geno1=(G;G)
|geno2=(G;T)
|geno3=(T;T)
|Gene_s=NADSYN1
}}{{ population diversity
| geno1=(G;G)
| geno2=(G;T)
| geno3=(T;T)
| CEU | 8.8 | 37.2 | 54.0
| HCB | 21.9 | 56.2 | 21.9
| JPT | 45.1 | 47.8 | 7.1
| YRI | 70.1 | 28.6 | 1.4
| ASW | 43.9 | 49.1 | 7.0
| CHB | 21.9 | 56.2 | 21.9
| CHD | 28.4 | 60.6 | 11.0
| GIH | 68.3 | 29.7 | 2.0
| LWK | 88.2 | 11.8 | 0.0
| MEX | 37.9 | 46.6 | 15.5
| MKK | 85.3 | 13.5 | 1.3
| TSI | 5.9 | 33.3 | 60.8
| HapMapRevision=28
}}[[rs12785878]], located near the 7-dehydrocholesterol reductase [[DHCR7]] gene on chromosome 11q12, has been linked by several studies to vitamin D serum concentrations.

In both studies, the allele associated with lower vitamin D, and thus the potential for [[vitamin D insufficiency]], is [[rs12785878]](G). Carriers of two such alleles have lower vitamin D than carriers of one allele, who in turn on average have lower vitamin D levels than [[rs12785878]](T;T) individuals.{{doi|10.1016/S0140-6736(10)60588-0}}

A near-perfect proxy (i.e. substitute) for [[rs12785878]] appears to be [[rs7944926]].

{{PMID Auto GWAS
|PMID=20541252
|Trait=Vitamin D insufficiency
|Title=Common genetic determinants of vitamin D insufficiency: a genome-wide association study.
|RiskAllele=
|Pval=2E-27
|OR=None
|ORtxt=None
|OA=1
}}

{{PMID Auto
|PMID=22130326
|Title=ANKRD55 and DHCR7 are novel multiple sclerosis risk loci
}}
{{PMID Auto
|PMID=22613962
|Title=Genetic Influences on Vitamin D Status and Forearm Fracture Risk in African American Children.
|OA=1
}}

{{PMID Auto
|PMID=22701574
|Title=Instrumental variable estimation of the causal effect of plasma 25-hydroxy-vitamin D on colorectal cancer risk: a mendelian randomization analysis
|OA=1
}}

{{PMID Auto
|PMID=23734184
|Title=Genetic Analyses Reveal a Role for Vitamin D Insufficiency in HCV-Associated Hepatocellular Carcinoma Development
|OA=1
}}

{{PMID Auto
|PMID=23924835
|Title=Genetic variant in vitamin D binding protein is associated with serum 25-hydroxyvitamin D and vitamin D insufficiency in southern Chinese
}}

{{PMID Auto
|PMID=23979957
|Title=Association between vitamin D metabolism gene polymorphisms and risk of islet autoimmunity and progression to type 1 diabetes: the diabetes autoimmunity study in the young (DAISY)
}}

{{PMID Auto
|PMID=22801813
|Title=The GC, CYP2R1 and DHCR7 genes are associated with vitamin D levels in northeastern Han Chinese children.
}}

{{PMID Auto
|PMID=23319826
|Title=Vitamin D and mortality: a Mendelian randomization study.
}}

{{PMID Auto
|PMID=23730842
|Title=Association of vitamin D serum levels and its common genetic determinants, with severity of liver fibrosis in genotype 1 chronic hepatitis C patients.
}}

{{PMID Auto
|PMID=23793229
|Title=Association of common gene variants in vitamin D modulating genes and colon cancer recurrence.
}}

{{on chip | Affy GenomeWide 6}}