Table 2.
Previously published genetic studies assessing vitamin B12 levels
| Study | Samples | N | Genomewide significant loci |
|---|---|---|---|
| Studies included in the current analysis | |||
| Tanaka et al. 2009 [7] | Discovery: SardiNIA + InCHIANTI + BLSA Replication: Progetto Nutrizione study |
N∼3000 + ∼700 in replication | FUT2 |
| Hazra et al. 2009 [8] | European Meta-analysis: women in NHS-CGEMS + men & women in SHARe | N∼4700 | FUT2, CUBN, TCN1, MUT |
| Grarup et al. 2013 [5] | Discovery: Icelandic (1K WGS; impute rest) + Danish exome |
N∼37K WGS + N∼8K Danish exome | FUT2, CD320, TCN1, TCN2, ABCD4, MMAA, MMACHC, MUT, MTHFR |
| Keene et al. 2014 [9] | Stroke patients in the Vitamin Intervention for Stroke Prevention trial | N ∼2100 | CUBN, TCN1 |
| Studies not included due to non-European ancestry samples | |||
| Lin et al. 2012 [10] | Discovery: Chinese men Replication: independent Chinese population |
N∼2000 + ∼1500 in replication | MS4A3, CLYBL, FUT6, 5q32, FUT2 |
| Nongmaithem et al. 2017 [11] | Discovery: Pune Maternal Nutrition Study Replication: Other Indian cohorts |
N∼1000 + ∼3400 in replication | FUT6, FUT2, TCN1, TCN2, CUBN, MMAA |
Abbreviation: SHARe, Framingham SNP Health Association Resource.