NM_000548.5:c.-65G>C

Variant names:

• chr16-2048030-G-C
• rs563544506
• NM_000548.5:c.-65G>C

Variant summary

Our verdict is Benign. Variant got -20 ACMG points: 0P and 20B. BP4_Strong BP6_Very_Strong BS1 BS2

The NM_000548.5(TSC2):​c.-65G>C variant causes a 5 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00223 in 1,441,468 control chromosomes in the GnomAD database, including 20 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★).

• Frequency:
  • Genomes: 𝑓 0.0033 (5 hom., cov: 33)
  • Exomes 𝑓: 0.0021 (15 hom.)
• Consequence: TSC2 NM_000548.5 5_prime_UTR
• Clinical Significance: Benign/Likely benign criteria provided, multiple submitters, no conflicts B:3
• Conservation: PhyloP100: 0.321

Genes affected

TSC2 (HGNC:12363): (TSC complex subunit 2) This gene is a tumor suppressor gene that encodes the growth inhibitory protein tuberin. Tuberin interacts with hamartin to form the TSC protein complex which functions in the control of cell growth. This TSC protein complex negatively regulates mammalian target of rapamycin complex 1 (mTORC1) signaling which is a major regulator of anabolic cell growth. Mutations in this gene have been associated with tuberous sclerosis and lymphangioleiomyomatosis. [provided by RefSeq, May 2022]

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]

ACMG classification

Verdict is Benign. Variant got -20 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.9).
• BP6: Variant 16-2048030-G-C is Benign according to our data. Variant chr16-2048030-G-C is described in ClinVar as [Likely_benign]. Clinvar id is 318303.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• BS1: Variant frequency is greater than expected in population nfe. gnomad4 allele frequency = 0.00326 (497/152294) while in subpopulation NFE AF= 0.00204 (139/68010). AF 95% confidence interval is 0.00177. There are 5 homozygotes in gnomad4. There are 304 alleles in male gnomad4 subpopulation. Median coverage is 33. This position pass quality control queck.
• BS2: High AC in GnomAd4 at 497 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TSC2	NM_000548.5	c.-65G>C		5_prime_UTR_variant	Exon 1 of 42	ENST00000219476.9	NP_000539.2
NTHL1	NM_002528.7	c.-207C>G		upstream_gene_variant		ENST00000651570.2	NP_002519.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
TSC2	ENST00000219476	c.-65G>C		5_prime_UTR_variant	Exon 1 of 42	5	NM_000548.5	ENSP00000219476.3
NTHL1	ENST00000651570.2	c.-207C>G		upstream_gene_variant			NM_002528.7	ENSP00000498421.1

Frequencies

GnomAD3 genomes AF: 0.00327 AC: 497 AN: 152186 Hom.: 5 Cov.: 33

Gnomad AFR AF: 0.000121

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000524

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.000827

Gnomad FIN AF: 0.0318

Gnomad MID AF: 0.00318

Gnomad NFE AF: 0.00204

Gnomad OTH AF: 0.000956

GnomAD4 exome AF: 0.00211 AC: 2719 AN: 1289174 Hom.: 15 Cov.: 31 AF XY: 0.00206 AC XY: 1296 AN XY: 627958

Gnomad4 AFR exome AF: 0.000307

Gnomad4 AMR exome AF: 0.000537

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000310

Gnomad4 SAS exome AF: 0.00115

Gnomad4 FIN exome AF: 0.0268

Gnomad4 NFE exome AF: 0.00162

Gnomad4 OTH exome AF: 0.00222

GnomAD4 genome AF: 0.00326 AC: 497 AN: 152294 Hom.: 5 Cov.: 33 AF XY: 0.00408 AC XY: 304 AN XY: 74460

Gnomad4 AFR AF: 0.000120

Gnomad4 AMR AF: 0.000523

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.000827

Gnomad4 FIN AF: 0.0318

Gnomad4 NFE AF: 0.00204

Gnomad4 OTH AF: 0.000946

Alfa AF: 0.00244 Hom.: 0

Bravo AF: 0.00103

ClinVar

Significance: Benign/Likely benign

Submissions summary: Benign:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Benign:2

Jun 01, 2023

CeGaT Center for Human Genetics Tuebingen

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

TSC2: BS1 -

Jul 20, 2018

GeneDx

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Tuberous sclerosis syndrome Benign:1

Jan 12, 2018

Illumina Laboratory Services, Illumina

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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 benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.90
CADD	Benign	9.0
DANN	Benign	0.59

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

Publications

LitVar

Other links and lift over

dbSNP: rs563544506; hg19: chr16-2098031;