chr17-31155970-C-CTT

Variant names:

• chr17-31155970-C-CTT
• rs551568608
• NM_001042492.3:c.61-5_61-4dupTT

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2

The NM_001042492.3(NF1):​c.61-5_61-4dupTT variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000144 in 1,386,728 control chromosomes in the GnomAD database, with no homozygous occurrence. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: NF1 NM_001042492.3 splice_region, intron
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -0.175
• Publications: 0 publications found

Genes affected

NF1 (HGNC:7765): (neurofibromin 1) This gene product appears to function as a negative regulator of the ras signal transduction pathway. Mutations in this gene have been linked to neurofibromatosis type 1, juvenile myelomonocytic leukemia and Watson syndrome. The mRNA for this gene is subject to RNA editing (CGA>UGA->Arg1306Term) resulting in premature translation termination. Alternatively spliced transcript variants encoding different isoforms have also been described for this gene. [provided by RefSeq, Jul 2008]

NF1 Gene-Disease associations (from GenCC):

• neurofibromatosis type 1

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), ClinGen, PanelApp Australia, G2P, Genomics England PanelApp
• neurofibromatosis-Noonan syndrome

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, Genomics England PanelApp, PanelApp Australia
• Moyamoya disease

  Inheritance: AD Classification: MODERATE Submitted by: Genomics England PanelApp
• hereditary pheochromocytoma-paraganglioma

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• familial ovarian cancer

  Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

ACMG classification

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
NF1	NM_001042492.3	c.61-5_61-4dupTT		splice_region_variant, intron_variant	Intron 1 of 57	ENST00000358273.9	NP_001035957.1
NF1	NM_000267.4	c.61-5_61-4dupTT		splice_region_variant, intron_variant	Intron 1 of 56		NP_000258.1
NF1	NM_001128147.3	c.61-5_61-4dupTT		splice_region_variant, intron_variant	Intron 1 of 14		NP_001121619.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
NF1	ENST00000358273.9	c.61-13_61-12insTT		intron_variant	Intron 1 of 57	1	NM_001042492.3	ENSP00000351015.4

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome AF: 0.00000144 AC: 2 AN: 1386728 Hom.: 0 Cov.: 33 AF XY: 0.00000145 AC XY: 1 AN XY: 689550

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 30208

American (AMR) AF: 0.00 AC: 0 AN: 36248

Ashkenazi Jewish (ASJ) AF: 0.0000412 AC: 1 AN: 24264

East Asian (EAS) AF: 0.00 AC: 0 AN: 36648

South Asian (SAS) AF: 0.00 AC: 0 AN: 79618

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 48026

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5372

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1069712

Other (OTH) AF: 0.0000177 AC: 1 AN: 56632

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 31

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
PhyloP100		-0.17

Splicing

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

Other links and lift over

dbSNP: rs551568608; hg19: chr17-29482988;