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#Summary statistics for GWAS analysis of 215 DTI parameters (110 mean parameters + 105 PC parameters, see below)
#Bingxin Zhao (bingxin@unc.edu)
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Sample size n=33,292 (UKB British cohort)
Number of reported SNPs p~9,023,710 (Chromosomes 1-22)
Version: July15, 2020
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GWAS was performed by fastGWA: https://cnsgenomics.com/software/gcta/index.html#fastGWA/

Each file contains the following columns:

#CHR       Chromosome
#SNP       SNP identifier
#POS       Physical position (base-pair)
#A1        Tested allele (minor allele by default) 
#A2        Null allele
#N         Per-SNP Sample Size
#AF1       Frequency of A1
#BETA      SNP effect 
#SE        SNP SE 
#Z         SNP Z-score
#P         P-value from fastGWA
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110 DTI Mean parameters for 21 WM tracts and the whole brain average (22*5=110)
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# WM tracts (21) + whole brain average (22 in total)
ID	Full Name
ACR	Anterior corona radiata
ALIC	Anterior limb of internal capsule
BCC	Body of corpus callosum
CGC	Cingulum (cingulate gyrus) 
CGH	Cingulum (hippocampus) 
CST	Corticospinal tract 
EC	External capsule 
FX	Fornix (column and body of fornix)
FXST	Fornix (cres) / Stria terminalis (can not be resolved with current resolution) 
GCC	Genu of corpus callosum
IFO	Inferior fronto-occipital fasciculus
PCR	Posterior corona radiata 
PLIC	Posterior limb of internal capsule
PTR	Posterior thalamic radiation (include optic radiation) 
RLIC	Retrolenticular part of internal capsule
SCC	Splenium of corpus callosum
SCR	Superior corona radiata
SFO	Superior fronto-occipital fasciculus (could be a part of anterior internal capsule) 
SLF	Superior longitudinal fasciculus
SS	Sagittal stratum (include inferior longitidinal fasciculus and inferior fronto-occipital fasciculus)
UNC	Uncinate fasciculus
Average	Whole brain average across all tracts
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# DTI parameters (5)
DTI parameter	 Full name 	Description
FA	fractional anisotropy	a summary measure of WM integrity
MD	mean diusivities 	magnitude of absolute directionality
AD	axial diusivities	eigenvalue of the principal diusion direction
RD	radial diusivities	average of the eigenvalues of the two secondary directions
MO	mode of anisotropy	third moment of the tensor
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105 DTI PC parameters (21*5=105)
For the 21 WM tracts listed above, we also perform analysis for the top five principle components (PCs) of the FA measure.  
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The detailed list of these 215 files can be found in the DTI.csv file while downloading the GWAS summary statistics via wget.  
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Reference:

Zhao et al (2020) Common genetic variation influencing human white matter microstructure. https://doi.org/10.1101/2020.05.23.112409

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This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License (https://creativecommons.org/licenses/by-nc-sa/4.0/)

Particularly, you agree not to attempt to identify individual participants and not to use these data for projects that may lead to stigmatizing individuals or groups of individuals.

When reporting results of research that utilizes these data, we request that you cite the original publication.

Commercial use: If you want to use the GWAS sumstats commercially, you must first get our permission to do so. Please send an e-mail to Hongtu Zhu (htzhu@email.unc.edu).