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.bim

Extended variant map with .bed: CHR, SNP, CM, BP, A1 (first/clear-bit allele, usually minor), A2 (second/set-bit allele, usually major). PLINK 2 .bim lists ALT before REF but encodes the same roles as 1.x A1/A2.

Overview

Field Value
Format key plink_bim
Spec file formats/plink_bim.json
Cite name PLINK 1.9
Version PLINK 1.9 (doc revision 19 Aug 2025)
Last checked 20260326
Source https://www.cog-genomics.org/plink/1.9/formats#bim
Citation Purcell, S., Neale, B., Todd-Brown, K., Thomas, L., Ferreira, M. A., Bender, D., ... & Sham, P. C. (2007). PLINK: a tool set for whole-genome association and population-based linkage analyses. The American journal of human genetics, 81(3), 559-575.
## File layout
Field Value
Separator TAB
Header row no
Column order 0, 1, 2, 3, 4, 5
## Column mapping
Raw header Canonical
0 CHR
1 SNPID
2 CM
3 POS
4 EA
5 NEA
## Header descriptions
Column Description
0 Chromosome code
1 Variant identifier
2 Genetic distance in morgans (often 0)
3 Base-pair coordinate (1-based)
4 Allele 1 (minor in .bed; first allele)
5 Allele 2 (major in .bed; second allele)
## Coverage

3/9 tier groups satisfied.

Tier Status Matched Missing
Variant ID yes SNPID rsID
Genomic location yes CHR, POS
Effect / other allele yes EA, NEA
Effect size no BETA, OR, HR, Z
Uncertainty no SE
P-value no P, MLOG10P
Sample size no N, N_CASE
Allele frequency no EAF, MAF, NEAF
Imputation / QC no INFO
## See also