chr1-3857657-G-T

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 2P and 1B. PM2BP4

The NM_004402.4(DFFB):​c.54G>T​(p.Lys18Asn) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000125 in 1,599,728 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 34)
Exomes 𝑓: 0.000012 ( 0 hom. )

Consequence

DFFB
NM_004402.4 missense

Scores

4
6
9

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 0.642

Publications

0 publications found
Variant links:
Genes affected
DFFB (HGNC:2773): (DNA fragmentation factor subunit beta) Apoptosis is a cell death process that removes toxic and/or useless cells during mammalian development. The apoptotic process is accompanied by shrinkage and fragmentation of the cells and nuclei and degradation of the chromosomal DNA into nucleosomal units. DNA fragmentation factor (DFF) is a heterodimeric protein of 40-kD (DFFB) and 45-kD (DFFA) subunits. DFFA is the substrate for caspase-3 and triggers DNA fragmentation during apoptosis. DFF becomes activated when DFFA is cleaved by caspase-3. The cleaved fragments of DFFA dissociate from DFFB, the active component of DFF. DFFB has been found to trigger both DNA fragmentation and chromatin condensation during apoptosis. Alternatively spliced transcript variants encoding distinct isoforms have been found for this gene but the biological validity of some of these variants has not been determined. [provided by RefSeq, Sep 2013]

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 1 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.4118029).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
DFFBNM_004402.4 linkc.54G>T p.Lys18Asn missense_variant Exon 1 of 7 ENST00000378209.8 NP_004393.1 O76075-1Q96P73

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
DFFBENST00000378209.8 linkc.54G>T p.Lys18Asn missense_variant Exon 1 of 7 1 NM_004402.4 ENSP00000367454.4 O76075-1

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152232
Hom.:
0
Cov.:
34
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000294
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000132
AC:
3
AN:
228018
AF XY:
0.00
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000291
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000124
AC:
18
AN:
1447496
Hom.:
0
Cov.:
31
AF XY:
0.0000111
AC XY:
8
AN XY:
719390
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
32854
American (AMR)
AF:
0.00
AC:
0
AN:
43168
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25814
East Asian (EAS)
AF:
0.00
AC:
0
AN:
38716
South Asian (SAS)
AF:
0.00
AC:
0
AN:
83974
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
51766
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5726
European-Non Finnish (NFE)
AF:
0.0000154
AC:
17
AN:
1105750
Other (OTH)
AF:
0.0000167
AC:
1
AN:
59728
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.500
Heterozygous variant carriers
0
1
2
3
4
5
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000131
AC:
2
AN:
152232
Hom.:
0
Cov.:
34
AF XY:
0.0000269
AC XY:
2
AN XY:
74372
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41466
American (AMR)
AF:
0.00
AC:
0
AN:
15290
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5182
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4836
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10628
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000294
AC:
2
AN:
68044
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.600
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.0000189
ExAC
AF:
0.0000166
AC:
2

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

not specified Uncertain:1
Mar 20, 2025
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.54G>T (p.K18N) alteration is located in exon 1 (coding exon 1) of the DFFB gene. This alteration results from a G to T substitution at nucleotide position 54, causing the lysine (K) at amino acid position 18 to be replaced by an asparagine (N). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.86
BayesDel_addAF
Benign
-0.16
T
BayesDel_noAF
Benign
-0.38
CADD
Uncertain
25
DANN
Uncertain
1.0
DEOGEN2
Benign
0.38
T;T;D;.
Eigen
Uncertain
0.33
Eigen_PC
Uncertain
0.22
FATHMM_MKL
Benign
0.55
D
LIST_S2
Benign
0.81
T;T;T;T
M_CAP
Pathogenic
0.30
D
MetaRNN
Benign
0.41
T;T;T;T
MetaSVM
Benign
-0.57
T
MutationAssessor
Uncertain
2.9
.;.;M;.
PhyloP100
0.64
PrimateAI
Uncertain
0.70
T
PROVEAN
Uncertain
-3.7
.;D;D;D
REVEL
Benign
0.26
Sift
Pathogenic
0.0
.;D;D;D
Sift4G
Pathogenic
0.0
D;D;D;D
Polyphen
1.0, 0.99
.;D;D;.
Vest4
0.41
MutPred
0.56
Loss of methylation at K18 (P = 0.0034);Loss of methylation at K18 (P = 0.0034);Loss of methylation at K18 (P = 0.0034);Loss of methylation at K18 (P = 0.0034);
MVP
0.62
MPC
0.82
ClinPred
0.98
D
GERP RS
1.9
PromoterAI
-0.045
Neutral
Varity_R
0.84
gMVP
0.75
Mutation Taster
=59/41
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.0
Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

Other links and lift over

dbSNP: rs762567083; hg19: chr1-3774221; API