NM_024675.4:c.1188C>G

Variant names:

• chr16-23635358-G-C
• rs587780817
• NM_024675.4:c.1188C>G

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PM2 PP3

The NM_024675.4(PALB2):​c.1188C>G​(p.Cys396Trp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,642 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic 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. C396Y) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: PALB2 NM_024675.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: -0.0590
• Publications: 3 publications found

Genes affected

PALB2 (HGNC:26144): (partner and localizer of BRCA2) This gene encodes a protein that may function in tumor suppression. This protein binds to and colocalizes with the breast cancer 2 early onset protein (BRCA2) in nuclear foci and likely permits the stable intranuclear localization and accumulation of BRCA2. [provided by RefSeq, Jul 2008]

PALB2 Gene-Disease associations (from GenCC):

• hereditary breast carcinoma

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen, Ambry Genetics
• Fanconi anemia complementation group N

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae), ClinGen, Ambry Genetics
• pancreatic cancer, susceptibility to, 3

  Inheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp, Labcorp Genetics (formerly Invitae)
• familial ovarian cancer

  Inheritance: AD Classification: MODERATE Submitted by: ClinGen
• Fanconi anemia

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• hereditary nonpolyposis colon cancer

  Inheritance: AD Classification: LIMITED Submitted by: ClinGen

ACMG classification

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.831

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_024675.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	PALB2	NM_024675.4	MANE Select	c.1188C>G	p.Cys396Trp	missense	Exon 4 of 13	NP_078951.2
	PALB2	NM_001407296.1		c.1128C>G	p.Cys376Trp	missense	Exon 3 of 12	NP_001394225.1
	PALB2	NM_001407297.1		c.1188C>G	p.Cys396Trp	missense	Exon 4 of 12	NP_001394226.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	PALB2	ENST00000261584.9	TSL:1 MANE Select	c.1188C>G	p.Cys396Trp	missense	Exon 4 of 13	ENSP00000261584.4
	PALB2	ENST00000568219.5	TSL:1	c.303C>G	p.Cys101Trp	missense	Exon 4 of 13	ENSP00000454703.2
	PALB2	ENST00000561514.3	TSL:5	c.1194C>G	p.Cys398Trp	missense	Exon 4 of 13	ENSP00000460666.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461642 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 727126

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26132

East Asian (EAS) AF: 0.00 AC: 0 AN: 39698

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53188

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1112000

Other (OTH) AF: 0.00 AC: 0 AN: 60394

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Familial cancer of breast Uncertain:1

Jul 16, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt PALB2 protein function. ClinVar contains an entry for this variant (Variation ID: 841874). This variant has not been reported in the literature in individuals affected with PALB2-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces cysteine, which is neutral and slightly polar, with tryptophan, which is neutral and slightly polar, at codon 396 of the PALB2 protein (p.Cys396Trp).

Hereditary cancer-predisposing syndrome Uncertain:1

Apr 20, 2024

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.C396W variant (also known as c.1188C>G), located in coding exon 4 of the PALB2 gene, results from a C to G substitution at nucleotide position 1188. The cysteine at codon 396 is replaced by tryptophan, an amino acid with highly dissimilar properties. This amino acid position is not well conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear.

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.38
BayesDel_addAF	Benign	-0.023	T
BayesDel_noAF	Benign	-0.27
CADD	Benign	20
DANN	Uncertain	0.99
DEOGEN2	Benign	0.20	T
Eigen	Uncertain	0.20
Eigen_PC	Benign	0.076
FATHMM_MKL	Uncertain	0.84	D
LIST_S2	Benign	0.71	T
M_CAP	Benign	0.031	D
MetaRNN	Pathogenic	0.83	D
MetaSVM	Benign	-0.92	T
MutationAssessor	Benign	1.8	L
PhyloP100		-0.059
PrimateAI	Uncertain	0.51	T
PROVEAN	Pathogenic	-7.4	D
REVEL	Benign	0.23
Sift	Uncertain	0.0070	D
Sift4G	Uncertain	0.0060	D
Polyphen		1.0	D
Vest4		0.69
MutPred		0.78		Gain of catalytic residue at P399 (P = 0.0237)
MVP		0.51
MPC		0.39
ClinPred		0.99	D
GERP RS		-0.93
Varity_R		0.65
gMVP		0.68

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

Other links and lift over

dbSNP: rs587780817; hg19: chr16-23646679;