12-66304921-C-T

Variant names:

• chr12-66304921-C-T
• rs376823726
• NM_001370285.1:c.378C>T

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 2P and 5B. PM2 BP4_Strong BP7

The NM_001370285.1(HELB):​c.378C>T​(p.Ile126Ile) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,778 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: HELB NM_001370285.1 synonymous
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -0.151
• Publications: 0 publications found

Genes affected

HELB (HGNC:17196): (DNA helicase B) This gene encodes a DNA-dependent ATPase which catalyzes the unwinding of DNA necessary for DNA replication, repair, recombination, and transcription. This gene is thought to function specifically during the S phase entry of the cell cycle. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Feb 2016]

HELB Gene-Disease associations (from GenCC):

• familial ovarian carcinoma

  Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics

ACMG classification

Our verdict: Likely_benign. The variant received -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.69).
• BP7: Synonymous conserved (PhyloP=-0.151 with no splicing effect.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001370285.1. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	HELB	NM_001370285.1	MANE Select	c.378C>T	p.Ile126Ile	synonymous	Exon 2 of 13	NP_001357214.1	Q8NG08-1
	HELB	NM_033647.5		c.378C>T	p.Ile126Ile	synonymous	Exon 2 of 14	NP_387467.2
	HELB	NR_135080.2		n.489C>T		non_coding_transcript_exon	Exon 2 of 13

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	HELB	ENST00000247815.9	TSL:1 MANE Select	c.378C>T	p.Ile126Ile	synonymous	Exon 2 of 13	ENSP00000247815.5	Q8NG08-1
	HELB	ENST00000440906.6	TSL:1	n.378C>T		non_coding_transcript_exon	Exon 2 of 12	ENSP00000396955.2	Q8NG08-2
	HELB	ENST00000542394.5	TSL:1	n.378C>T		non_coding_transcript_exon	Exon 2 of 13	ENSP00000439617.1	F5H1I4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461778 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 727198

African (AFR) AF: 0.00 AC: 0 AN: 33478

American (AMR) AF: 0.00 AC: 0 AN: 44722

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

East Asian (EAS) AF: 0.00 AC: 0 AN: 39686

South Asian (SAS) AF: 0.00 AC: 0 AN: 86256

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53418

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

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1111928

Other (OTH) AF: 0.00 AC: 0 AN: 60390

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.69
CADD	Benign	6.9
DANN	Benign	0.61
PhyloP100		-0.15

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		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: rs376823726; hg19: chr12-66698701; COSMIC: COSV99921634;