gnomAD reports variants with "NA" allele count and allele frequency
0
2
Entering edit mode
4.6 years ago
j.lunger18 ▴ 30

I recently downloaded sliced variant .vcf files from gnomAD. Upon downstream analysis, I noticed that some of my variants were annotated to have no reported allele count or allele frequency... Does anyone know how this could be? I assumed that if there was no count for this allele, the allele would not be in the file?

AApos
<fctr>
Type
<fctr>
change
<fctr>
non_cancer_AF
<fctr>
AF
<fctr>
AC
<fctr>
275 Missense    p.Leu275Ser 0.00000e+00 NA  NA
278 Frameshift  p.Lys278fs  4.78973e-06 9.42454e-06 1
281 Missense    p.Phe281Leu 4.83311e-06 NA  NA
282 STOP Gain   p.Gln282*   0.00000e+00 NA  NA
282 Missense    p.Gln282Glu 4.86485e-06 9.51059e-06 1
285 Frameshift and Splice   p.Lys285fs  4.86282e-06 6.56944e-05 1
291 Synonymous  p.Gly291Gly 8.44602e-06 3.26648e-05 1
293 Synonymous  p.Lys293Lys 4.22244e-06 2.89218e-05 1
296 Synonymous  p.Val296Val 4.22215e-06 8.79678e-06 1
297 Synonymous  p.Lys297Lys 1.26659e-05 2.63894e-05 3
1-10 of 28 rows
gnomAD SNPs vcf • 1.3k views
ADD COMMENT
0
Entering edit mode

give us an example please (build/CHROM;POS)

ADD REPLY
0
Entering edit mode

CHROM is 4. I downloaded from gnomAD exomes v2.1.1. When I searched rs779360656 in gnomAD, it shows that the allele frequency should be 0.000004518. Is it possible that I downloaded the genomes file by accident and the variants from exomes shows up?

119625175   T   C   275 rs1192393794    Missense    0.00000e+00 NA  NA  
    119625181   CA  C   278 rs1418157431    Frameshift  4.78973e-06 9.42454e-06 1   
    119625194   T   G   281 rs779360656 Missense    4.83311e-06 NA  NA  
    119625195   C   T   282 rs1165412269    STOP Gain   0.00000e+00 NA  NA  
    119625195   C   G   282 rs1165412269    Missense    4.86485e-06 9.51059e-06 1

https://gnomad.broadinstitute.org/variant/4-119625194-T-G?dataset=gnomad_r2_1

ADD REPLY
0
Entering edit mode

Did you ever figure this out? I have the same question.

gnomAD AF = 0 vs gnomAD AF = NA (gnomad V2)

I have proof showing its not just an error, that there is just not an entry despite it looking like there is coverage there.

ADD REPLY

Login before adding your answer.

Traffic: 1869 users visited in the last hour
Help About
FAQ
Access RSS
API
Stats

Use of this site constitutes acceptance of our User Agreement and Privacy Policy.

Powered by the version 2.3.6