6-18120699-A-G

Variant summary

Our verdict is Benign. Variant got -8 ACMG points: 2P and 10B. PM2 BP4_Strong BP6_Moderate BS1

The NM_198586.3(NHLRC1):c.*720T>C variant causes a 3 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000867 in 152,332 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★).

• Frequency:
  • Genomes: 𝑓 0.00087 (1 hom., cov: 33)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: NHLRC1 NM_198586.3 3_prime_UTR
• Clinical Significance: Likely benign criteria provided, single submitter B:1
• Conservation: PhyloP100: 0.335

Genes affected

NHLRC1 (HGNC:21576): (NHL repeat containing E3 ubiquitin protein ligase 1) The protein encoded by this gene is a single subunit E3 ubiquitin ligase. Laforin is polyubiquitinated by the encoded protein. Defects in this intronless gene lead to an accumulation of laforin and onset of Lafora disease, also known as progressive myoclonic epilepsy type 2 (EPM2).[provided by RefSeq, Mar 2010]

ACMG classification

Verdict is Benign. Variant got -8 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.86).
• BP6: Variant 6-18120699-A-G is Benign according to our data. Variant chr6-18120699-A-G is described in ClinVar as [Likely_benign]. Clinvar id is 356060.Status of the report is criteria_provided_single_submitter, 1 stars.
• BS1: Variant frequency is greater than expected in population eas. gnomad4 allele frequency = 0.000867 (132/152332) while in subpopulation EAS AF= 0.0195 (101/5180). AF 95% confidence interval is 0.0164. There are 1 homozygotes in gnomad4. There are 85 alleles in male gnomad4 subpopulation. Median coverage is 33. This position pass quality control queck.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
NHLRC1	NM_198586.3	c.*720T>C		3_prime_UTR_variant	1/1	ENST00000340650.6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
NHLRC1	ENST00000340650.6	c.*720T>C		3_prime_UTR_variant	1/1		NM_198586.3	P1

Frequencies

GnomAD3 genomes AF: 0.000867 AC: 132 AN: 152214 Hom.: 1 Cov.: 33

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.0000654

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.0195

Gnomad SAS AF: 0.000414

Gnomad FIN AF: 0.000282

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.000353

Gnomad OTH AF: 0.000478

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 220 Hom.: 0 Cov.: 0 AF XY: 0.00 AC XY: 0 AN XY: 110

Gnomad4 AMR 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: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.000867 AC: 132 AN: 152332 Hom.: 1 Cov.: 33 AF XY: 0.00114 AC XY: 85 AN XY: 74498

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.0000653

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.0195

Gnomad4 SAS AF: 0.000414

Gnomad4 FIN AF: 0.000282

Gnomad4 NFE AF: 0.000353

Gnomad4 OTH AF: 0.000473

Alfa AF: 0.000876 Hom.: 2

Bravo AF: 0.000903

Asia WGS AF: 0.00491 AC: 17 AN: 3478

ClinVar

Significance: Likely benign

Submissions summary: Benign:1

Revision: criteria provided, single submitter

Submissions by phenotype

Lafora disease Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 13, 2018

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as likely benign is not then subjected to further curation. The score for this variant resulted in a classification of likely benign for this disease. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.86
Cadd	Benign	1.5
Dann	Benign	0.82

Splicing

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

Publications

LitVar

Other links and lift over

dbSNP: rs141863990; hg19: chr6-18120930;