19-5623379-G-T

Position:

• chr19-5623379-G-T

Variant summary

Our verdict is Likely benign. Variant got -6 ACMG points: 0P and 6B. BP4_Moderate BS2

The NM_001320571.2(SAFB):​c.-26G>T variant causes a 5 prime UTR premature start codon gain change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000496 in 1,613,694 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: 32)
  • Exomes 𝑓: 0.0000041 (0 hom.)
• Consequence: SAFB NM_001320571.2 5_prime_UTR_premature_start_codon_gain
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 3.41

Genes affected

SAFB (HGNC:10520): (scaffold attachment factor B) This gene encodes a DNA-binding protein which has high specificity for scaffold or matrix attachment region DNA elements (S/MAR DNA). This protein is thought to be involved in attaching the base of chromatin loops to the nuclear matrix but there is conflicting evidence as to whether this protein is a component of chromatin or a nuclear matrix protein. Scaffold attachment factors are a specific subset of nuclear matrix proteins (NMP) that specifically bind to S/MAR. The encoded protein is thought to serve as a molecular base to assemble a 'transcriptosome complex' in the vicinity of actively transcribed genes. It is involved in the regulation of heat shock protein 27 transcription, can act as an estrogen receptor co-repressor and is a candidate for breast tumorigenesis. This gene is arranged head-to-head with a similar gene whose product has the same functions. Multiple transcript variants encoding different isoforms have been found for this gene.[provided by RefSeq, Jan 2011]

SAFB2 (HGNC:21605): (scaffold attachment factor B2) The protein encoded by this gene, along with its paralog (scaffold attachment factor B1), is a repressor of estrogen receptor alpha. The encoded protein binds scaffold/matrix attachment region (S/MAR) DNA and is involved in cell cycle regulation, apoptosis, differentiation, the stress response, and regulation of immune genes. [provided by RefSeq, May 2016]

ACMG classification

Verdict is Likely_benign. Variant got -6 ACMG points.

• BP4: Computational evidence support a benign effect (MetaRNN=0.20949915).
• BS2: High AC in GnomAdExome4 at 6 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
SAFB	NM_001201338.2	c.174G>T	p.Met58Ile	missense_variant	1/21	ENST00000588852.2	NP_001188267.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
SAFB	ENST00000588852.2	c.174G>T	p.Met58Ile	missense_variant	1/21	1	NM_001201338.2	ENSP00000467423.1

Frequencies

GnomAD3 genomes AF: 0.0000131 AC: 2 AN: 152220 Hom.: 0 Cov.: 32

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

GnomAD4 exome AF: 0.00000411 AC: 6 AN: 1461474 Hom.: 0 Cov.: 32 AF XY: 0.00000413 AC XY: 3 AN XY: 727016

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000540

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.0000131 AC: 2 AN: 152220 Hom.: 0 Cov.: 32 AF XY: 0.0000134 AC XY: 1 AN XY: 74368

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000294

Gnomad4 OTH AF: 0.00

Bravo AF: 0.0000151

EpiCase AF: 0.0000545

EpiControl AF: 0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Dec 07, 2024

The c.174G>T (p.M58I) alteration is located in exon 1 (coding exon 1) of the SAFB gene. This alteration results from a G to T substitution at nucleotide position 174, causing the methionine (M) at amino acid position 58 to be replaced by an isoleucine (I). 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	0.68
BayesDel_addAF	Benign	-0.18	T
BayesDel_noAF	Benign	-0.50
CADD	Pathogenic	27
DANN	Benign	0.96
DEOGEN2	Benign	0.16	T;.;.;.
Eigen	Benign	-0.044
Eigen_PC	Benign	0.0041
FATHMM_MKL	Benign	0.64	D
LIST_S2	Uncertain	0.95	D;D;D;D
M_CAP	Benign	0.032	D
MetaRNN	Benign	0.21	T;T;T;T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	0.36	N;N;N;N
PrimateAI	Uncertain	0.58	T
PROVEAN	Benign	-1.8	N;.;N;.
REVEL	Benign	0.094
Sift	Benign	0.21	T;.;T;.
Sift4G	Benign	1.0	T;T;T;T
Polyphen		0.97	D;.;.;.
Vest4		0.37
MutPred		0.43		Loss of MoRF binding (P = 0.1035);Loss of MoRF binding (P = 0.1035);Loss of MoRF binding (P = 0.1035);Loss of MoRF binding (P = 0.1035);
MVP		0.35
MPC		2.5
ClinPred		0.74	D
GERP RS		2.9
RBP_binding_hub_radar		0.92
RBP_regulation_power_radar		2.6
Varity_R		0.16
gMVP		0.16

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

LitVar

Other links and lift over

dbSNP: rs908891671; hg19: chr19-5623390;