rs765879627

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM2PP3_Strong

The NM_015474.4(SAMHD1):​c.494T>C​(p.Phe165Ser) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000031 in 1,613,960 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 13/22 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. F165L) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 31)
Exomes 𝑓: 0.0000027 ( 0 hom. )

Consequence

SAMHD1
NM_015474.4 missense

Scores

16
2

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1U:3

Conservation

PhyloP100: 9.32

Publications

1 publications found
Variant links:
Genes affected
SAMHD1 (HGNC:15925): (SAM and HD domain containing deoxynucleoside triphosphate triphosphohydrolase 1) This gene may play a role in regulation of the innate immune response. The encoded protein is upregulated in response to viral infection and may be involved in mediation of tumor necrosis factor-alpha proinflammatory responses. Mutations in this gene have been associated with Aicardi-Goutieres syndrome. [provided by RefSeq, Mar 2010]
SAMHD1 Gene-Disease associations (from GenCC):
  • Aicardi-Goutieres syndrome 5
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, PanelApp Australia, Labcorp Genetics (formerly Invitae), Genomics England PanelApp, G2P
  • Moyamoya disease
    Inheritance: AR Classification: STRONG Submitted by: Genomics England PanelApp
  • Aicardi-Goutieres syndrome
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • familial chilblain lupus
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • chilblain lupus 2
    Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics
  • chilblain lupus
    Inheritance: AD Classification: NO_KNOWN Submitted by: Illumina

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.972

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_015474.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
SAMHD1
NM_015474.4
MANE Select
c.494T>Cp.Phe165Ser
missense
Exon 4 of 16NP_056289.2
SAMHD1
NM_001363729.2
c.494T>Cp.Phe165Ser
missense
Exon 4 of 15NP_001350658.1
SAMHD1
NM_001363733.2
c.494T>Cp.Phe165Ser
missense
Exon 4 of 16NP_001350662.1

Ensembl Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
SAMHD1
ENST00000646673.2
MANE Select
c.494T>Cp.Phe165Ser
missense
Exon 4 of 16ENSP00000493536.2
SAMHD1
ENST00000262878.5
TSL:1
c.494T>Cp.Phe165Ser
missense
Exon 4 of 15ENSP00000262878.5
SAMHD1
ENST00000643918.1
c.494T>Cp.Phe165Ser
missense
Exon 4 of 16ENSP00000493928.1

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152116
Hom.:
0
Cov.:
31
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:
0.000207
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000398
AC:
1
AN:
251468
AF XY:
0.00000736
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:
0.00000879
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000274
AC:
4
AN:
1461844
Hom.:
0
Cov.:
30
AF XY:
0.00000138
AC XY:
1
AN XY:
727230
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26134
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39694
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53414
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000360
AC:
4
AN:
1111980
Other (OTH)
AF:
0.00
AC:
0
AN:
60394
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
1
1
2
2
3
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:
0.00000657
AC:
1
AN:
152116
Hom.:
0
Cov.:
31
AF XY:
0.0000135
AC XY:
1
AN XY:
74302
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41412
American (AMR)
AF:
0.00
AC:
0
AN:
15248
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3462
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5198
South Asian (SAS)
AF:
0.000207
AC:
1
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10612
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68036
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
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:
0.0000282
Hom.:
0
TwinsUK
AF:
0.000270
AC:
1
ALSPAC
AF:
0.00
AC:
0
ExAC
AF:
0.00000824
AC:
1

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:1Uncertain:3
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Aicardi-Goutieres syndrome 5 Pathogenic:1
Nov 12, 2025
Department of Molecular Genetics, Istishari Arab Hospital
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The SAMHD1 variant c.494T>C p.Phe165Ser creates an amino acid change from Phe to Ser at position 165. This variant is observed with very low frequency in the gnomAD v4.1.0 dataset (<0.001). This variant was previously reported in a patient with Aicardi-Goutieres syndrome (PMID: 35418820). It is classified as likely pathogenic (class 2) according to the recommendations of ACMG/AMP/ClinGen SVI guidelines.

not specified Uncertain:1
Jan 27, 2025
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: SAMHD1 c.494T>C (p.Phe165Ser) results in a non-conservative amino acid change in the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 4e-06 in 251468 control chromosomes (gnomAD). The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.494T>C has been reported in the literature in at least an individual affected with Aicardi Goutieres Syndrome where it was seen in trans with a pathogenic variant (Example: Oleksy_2022). To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. The following publication has been ascertained in the context of this evaluation (PMID: 35418820). ClinVar contains an entry for this variant (Variation ID: 445524). Based on the evidence outlined above, the variant was classified as uncertain significance.

Aicardi Goutieres syndrome Uncertain:1
May 27, 2021
Natera, Inc.
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

not provided Uncertain:1
May 12, 2017
Center for Pediatric Genomic Medicine, Children's Mercy Hospital and Clinics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.97
BayesDel_addAF
Pathogenic
0.58
D
BayesDel_noAF
Pathogenic
0.60
CADD
Pathogenic
29
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.92
D
Eigen
Pathogenic
0.88
Eigen_PC
Pathogenic
0.82
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Pathogenic
0.98
D
M_CAP
Pathogenic
0.79
D
MetaRNN
Pathogenic
0.97
D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Pathogenic
4.9
H
PhyloP100
9.3
PrimateAI
Pathogenic
0.85
D
PROVEAN
Pathogenic
-7.9
D
REVEL
Pathogenic
0.96
Sift
Pathogenic
0.0
D
Sift4G
Uncertain
0.033
D
Polyphen
1.0
D
Vest4
0.99
MutPred
0.81
Gain of disorder (P = 0.0039)
MVP
0.99
MPC
1.9
ClinPred
1.0
D
GERP RS
4.9
Varity_R
0.98
gMVP
0.90
Mutation Taster
=17/83
disease causing

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: rs765879627; hg19: chr20-35563447; API