20-36930760-C-T

Variant names:

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PP3_StrongPP5_Moderate

The NM_015474.4(SAMHD1):c.625G>A(p.Gly209Ser) variant causes a missense, splice region change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000005 in 1,601,102 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 15/26 in silico tools predict a damaging outcome for this variant. 2/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G209D) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0000048 ( 0 hom. )

Consequence

SAMHD1
NM_015474.4 missense, splice_region

Scores

Splicing: ADA: 1.000

Clinical Significance

Likely pathogenic criteria provided, single submitter P:2O:1

Conservation

PhyloP100: 7.81

Publications

8 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

SAMHD1 links:

Genome browser will be placed here

ACMG classification

Classification was made for transcript

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

PP3

Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF. Scorers claiming Uncertain: max_spliceai. No scorers claiming Benign.

PP5

Variant 20-36930760-C-T is Pathogenic according to our data. Variant chr20-36930760-C-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 4066.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SAMHD1	NM_015474.4 link	c.625G>A	p.Gly209Ser	missense_variant, splice_region_variant	Exon 5 of 16	ENST00000646673.2	NP_056289.2	Q9Y3Z3-1Q59H15
SAMHD1	NM_001363729.2 link	c.625G>A	p.Gly209Ser	missense_variant, splice_region_variant	Exon 5 of 15		NP_001350658.1
SAMHD1	NM_001363733.2 link	c.625G>A	p.Gly209Ser	missense_variant, splice_region_variant	Exon 5 of 16		NP_001350662.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SAMHD1	ENST00000646673.2 link	c.625G>A	p.Gly209Ser	missense_variant, splice_region_variant	Exon 5 of 16		NM_015474.4	ENSP00000493536.2		Q9Y3Z3-1

Frequencies

GnomAD3 genomes

AF:

0.00000658

AC:

AN:

151964

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000242

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:

0.00

Gnomad OTH

AF:

0.00

GnomAD2 exomes

AF:

0.00000398

AC:

AN:

251276

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:

0.00000880

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000483

AC:

AN:

1449138

Hom.:

Cov.:

AF XY:

0.00000416

AC XY:

AN XY:

721726

show subpopulations

African (AFR)

AF:

0.00

AC:

AN:

33178

American (AMR)

AF:

0.00

AC:

AN:

44716

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

26064

East Asian (EAS)

AF:

0.00

AC:

AN:

39624

South Asian (SAS)

AF:

0.00

AC:

AN:

85966

European-Finnish (FIN)

AF:

0.00

AC:

AN:

53260

Middle Eastern (MID)

AF:

0.00

AC:

AN:

5758

European-Non Finnish (NFE)

AF:

0.00000545

AC:

AN:

1100622

Other (OTH)

AF:

0.0000167

AC:

AN:

59950

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.446

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Exome Het

Variant carriers

<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:

0.00000658

AC:

AN:

151964

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

AN XY:

74192

show subpopulations

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.

African (AFR)

AF:

0.0000242

AC:

AN:

41374

American (AMR)

AF:

0.00

AC:

AN:

15250

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

3470

East Asian (EAS)

AF:

0.00

AC:

AN:

5186

South Asian (SAS)

AF:

0.00

AC:

AN:

4802

European-Finnish (FIN)

AF:

0.00

AC:

AN:

10580

Middle Eastern (MID)

AF:

0.00

AC:

AN:

316

European-Non Finnish (NFE)

AF:

0.00

AC:

AN:

67986

Other (OTH)

AF:

0.00

AC:

AN:

2088

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0.000000), which strongly suggests a high chance of mosaicism in these individuals.

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.375

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Alfa

AF:

0.0000148

Hom.:

Bravo

AF:

0.0000189

ExAC

AF:

0.00000824

AC:

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:2Other:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Aicardi-Goutieres syndrome 5

Pathogenic:2Other:1

Jan 06, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance:Likely pathogenic

Review Status:criteria provided, single submitter

Collection Method:clinical testing

This sequence change replaces glycine, which is neutral and non-polar, with serine, which is neutral and polar, at codon 209 of the SAMHD1 protein (p.Gly209Ser). This variant also falls at the last nucleotide of exon 5, which is part of the consensus splice site for this exon. This variant is present in population databases (rs121434516, gnomAD 0.0009%). This missense change has been observed in individuals with Aicardi-Gouti√®res syndrome (PMID: 19525956, 27943079). It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 4066). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is expected to disrupt SAMHD1 protein function with a positive predictive value of 95%. Experimental studies are conflicting or provide insufficient evidence to determine the effect of this variant on SAMHD1 function (PMID: 22461318, 24035396, 28229507). Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. -

Jul 01, 2009

OMIM

Significance:Pathogenic

Review Status:no assertion criteria provided

Collection Method:literature only

- -

GeneReviews

Significance:not provided

Review Status:no classification provided

Collection Method:literature only

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.97

BayesDel_addAF

Pathogenic

0.59

BayesDel_noAF

Pathogenic

0.61

CADD

Pathogenic

(source)

DANN

Uncertain

1.0

DEOGEN2

Uncertain

0.79

D;.;.;.

Eigen

Pathogenic

0.87

Eigen_PC

Pathogenic

0.80

FATHMM_MKL

Uncertain

0.96

LIST_S2

Pathogenic

1.0

.;D;D;D

M_CAP

Pathogenic

0.72

MetaRNN

Pathogenic

0.99

D;D;D;D

MetaSVM

Pathogenic

1.0

MutationAssessor

Pathogenic

4.1

H;H;.;H

PhyloP100

7.8

PrimateAI

Pathogenic

0.80

PROVEAN

Pathogenic

-5.9

.;D;.;.

REVEL

Pathogenic

0.92

Sift

Pathogenic

0.0

.;D;.;.

Sift4G

Pathogenic

0.0

.;D;.;.

Polyphen

1.0

D;.;.;.

Vest4

0.98

MutPred

0.96

Gain of disorder (P = 0.0994);Gain of disorder (P = 0.0994);Gain of disorder (P = 0.0994);Gain of disorder (P = 0.0994);

MVP

0.99

MPC

1.4

ClinPred

1.0

GERP RS

6.0

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Varity_R

0.95

gMVP

0.88

Mutation Taster

=6/94

disease causing

(source)

Splicing

Name

Calibrated prediction

Score

Prediction

dbscSNV1_ADA

Pathogenic

1.0

dbscSNV1_RF

Pathogenic

1.0

SpliceAI score (max)

0.45

Details are displayed if max score is > 0.2

DS_DL_spliceai

0.45

Position offset: 0

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

Publications

You must be logged in to view publications. This limit was set because tens of millions (!) of queries from AI bots are generated daily.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

Publications

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

Age Distribution

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

Other links and lift over