16-2039931-C-G

Variant names:

• chr16-2039931-C-G
• rs2084235801
• NM_002528.7:c.908G>C

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_002528.7(NTHL1):​c.908G>C​(p.Gly303Ala) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 16/22 in silico tools predict a benign 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. G303R) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 33)
• Consequence: NTHL1 NM_002528.7 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.813
• Publications: 0 publications found

Genes affected

NTHL1 (HGNC:8028): (nth like DNA glycosylase 1) The protein encoded by this gene is a DNA N-glycosylase of the endonuclease III family. Like a similar protein in E. coli, the encoded protein has DNA glycosylase activity on DNA substrates containing oxidized pyrimidine residues and has apurinic/apyrimidinic lyase activity. [provided by RefSeq, Oct 2008]

NTHL1 Gene-Disease associations (from GenCC):

• familial adenomatous polyposis 3

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Orphanet, Genomics England PanelApp, Ambry Genetics
• NTHL1-deficiency tumor predisposition syndrome

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
• breast cancer

  Inheritance: AR Classification: LIMITED Submitted by: Ambry Genetics
• meningioma

  Inheritance: AR Classification: LIMITED Submitted by: Ambry Genetics

ACMG classification

Our verdict: Likely_benign. The variant received -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.050506175).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
NTHL1	NM_002528.7	c.908G>C	p.Gly303Ala	missense_variant	Exon 6 of 6	ENST00000651570.2	NP_002519.2
NTHL1	NM_001318193.2	c.737G>C	p.Gly246Ala	missense_variant	Exon 5 of 5		NP_001305122.2
NTHL1	NM_001318194.2	c.578G>C	p.Gly193Ala	missense_variant	Exon 6 of 6		NP_001305123.1
NTHL1	XM_047434171.1	c.629G>C	p.Gly210Ala	missense_variant	Exon 6 of 6		XP_047290127.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
NTHL1	ENST00000651570.2	c.908G>C	p.Gly303Ala	missense_variant	Exon 6 of 6		NM_002528.7	ENSP00000498421.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Jan 21, 2020

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. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Not Avialable"; PolyPhen-2: "Benign"; Align-GVGD: "Not Available"). This variant has not been reported in the literature in individuals with NTHL1-related conditions. This variant is not present in population databases (ExAC no frequency). This sequence change replaces glycine with alanine at codon 311 of the NTHL1 protein (p.Gly311Ala). The glycine residue is weakly conserved and there is a small physicochemical difference between glycine and alanine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.081
BayesDel_addAF	Benign	-0.22	T
BayesDel_noAF	Benign	-0.55
CADD	Benign	7.9
DANN	Benign	0.67
DEOGEN2	Benign	0.11	T
Eigen	Benign	-1.1
Eigen_PC	Benign	-1.1
FATHMM_MKL	Benign	0.23	N
LIST_S2	Benign	0.59	T
M_CAP	Benign	0.0049	T
MetaRNN	Benign	0.051	T
MetaSVM	Benign	-0.97	T
MutationAssessor	Benign	-0.24	N
PhyloP100		0.81
PrimateAI	Benign	0.34	T
PROVEAN	Benign	0.46	N
REVEL	Benign	0.083
Sift	Benign	0.31	T
Sift4G	Benign	0.82	T
Polyphen		0.0070	B
Vest4		0.13
MutPred		0.21		Loss of catalytic residue at P307 (P = 0.1315);
MVP		0.061
MPC		0.067
ClinPred		0.084	T
GERP RS		2.9
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
Varity_R		0.031
gMVP		0.64
Mutation Taster		=99/1	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

Other links and lift over

dbSNP: rs2084235801; hg19: chr16-2089932;