2-17759978-C-T

Variant names:

• chr2-17759978-C-T
• NM_001130009.3:c.35C>T

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2 PP3

The NM_001130009.3(GEN1):​c.35C>T​(p.Pro12Leu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,461,778 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 (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: GEN1 NM_001130009.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.36

Genes affected

GEN1 (HGNC:26881): (GEN1 Holliday junction 5' flap endonuclease) This gene encodes a member of the Rad2/xeroderma pigmentosum group G nuclease family, whose members are characterized by N-terminal and internal xeroderma pigmentosum group G nuclease domains followed by helix-hairpin-helix domains and disordered C-terminal domains. The protein encoded by this gene is involved in resolution of Holliday junctions, which are intermediate four-way structures that covalently link DNA during homologous recombination and double-strand break repair. The protein resolves Holliday junctions by creating dual incisions across the junction to produce nicked duplex products that can be ligated. In addition, this protein has been found to localize to centrosomes where it has been implicated in regulation of centrosome integrity. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jul 2016]

SMC6 (HGNC:20466): (structural maintenance of chromosomes 6) Enables ubiquitin protein ligase binding activity. Involved in several processes, including cellular senescence; positive regulation of chromosome segregation; and telomere maintenance via recombination. Located in chromosome and nuclear body. Part of Smc5-Smc6 complex. [provided by Alliance of Genome Resources, Apr 2022]

ACMG classification

Verdict is Uncertain_significance. Variant got 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.822

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
GEN1	NM_001130009.3	c.35C>T	p.Pro12Leu	missense_variant	Exon 2 of 14	ENST00000381254.7	NP_001123481.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
GEN1	ENST00000381254.7	c.35C>T	p.Pro12Leu	missense_variant	Exon 2 of 14	5	NM_001130009.3	ENSP00000370653.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1461778 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 727206

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: 0.00000270

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Jan 05, 2025

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.P12L variant (also known as c.35C>T), located in coding exon 1 of the GEN1 gene, results from a C to T substitution at nucleotide position 35. The proline at codon 12 is replaced by leucine, an amino acid with similar properties. This amino acid position is conserved. In addition, the in silico prediction for this alteration is inconclusive. Based on the available evidence, the clinical significance of this variant remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.35
BayesDel_addAF	Pathogenic	0.21	D
BayesDel_noAF	Uncertain	0.060
CADD	Pathogenic	27
DANN	Uncertain	1.0
DEOGEN2	Benign	0.28	T;.;T;T
Eigen	Pathogenic	0.98
Eigen_PC	Pathogenic	0.91
FATHMM_MKL	Uncertain	0.96	D
LIST_S2	Uncertain	0.88	.;D;D;D
M_CAP	Benign	0.071	D
MetaRNN	Pathogenic	0.82	D;D;D;D
MetaSVM	Uncertain	0.0084	D
MutationAssessor	Pathogenic	3.8	H;.;H;.
PrimateAI	Uncertain	0.65	T
PROVEAN	Pathogenic	-8.7	D;D;D;D
REVEL	Uncertain	0.48
Sift	Uncertain	0.0010	D;D;D;D
Sift4G	Pathogenic	0.0	D;D;D;D
Polyphen		1.0	D;.;D;.
Vest4		0.79
MutPred		0.56		Gain of helix (P = 0.0854);Gain of helix (P = 0.0854);Gain of helix (P = 0.0854);Gain of helix (P = 0.0854);
MVP		0.77
MPC		0.24
ClinPred		1.0	D
GERP RS		5.4
Varity_R		0.94
gMVP		0.72

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.15		Details are displayed if max score is > 0.2

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

Publications

No publications associated with this variant yet.

Other links and lift over

hg19: chr2-17941245;